U3818DW, XPS 13 9370, DDM not working

Hi,

Am using a Dell XPS 13 9370 connected to the Dell U3818DW via HDMI and USB connected to the upstream port on the monitor. Not using the USB-C connection as I have that plugged into my Macbook Pro. I have been trying to get DDM working on my Dell XPS but cannot do so, either with DDM 1986 or 1995. The DDM Icon in the System Tray constantly says "Please connect a supported Dell Monitor."

Have attached my diagnostic log below for your reference. Have tried several of the solutions advised on this forum but have not had any success. Was able to have a successful connection between the Monitor & Firmware Update Package (Firmware was already updated), but not with DDM. Would appreciate your help. 

DDM 1995 Diagnostic Log:

Diagnostic Report, generated 19-May-20 (10.0.18363)
Copyright (c) 1995-2020, EnTech Taiwan.
Version = 1.50.0.1996
OS = 10.0.18363.2 x64
Mechanism = 3
Account = Standard
Command line = "C:\Program Files (x86)\Dell\Dell Display Manager\ddm.exe"
////////////////////////////////////////
LastCheck = 0x0000ABC2
HintShown = 0x00000001
AutoRestoreWindowLayout = 0x00000000
EnumErrorCount = 0x00000000
////////////////////////////////////////
21:24:03.566...Log opened
21:24:03.577...WinOS = 18363
21:24:03.664...LanguageID = 00000409 00000409 00000409
21:24:03.675...Build = 1.50.0.1996
21:24:03.677...Thunderbolt driver = tbt100x 17.4.79.11
21:24:03.678...Windows handles = 0001018A 00010126 00010190
21:24:03.680...OS monitor sleep timeout value = 600 ms.
21:24:03.681...Applied DPI = 96-106
21:24:03.681...VM = 0
21:24:03.682...Registered DDM popup hotkey = Shift+Ctrl+D 6044
21:24:03.683...Registered EA layout MRU hotkey = Shift+Ctrl+Home 6024
21:24:03.684...Registered application window hotkey = Shift+Ctrl+Ins 602D
21:24:03.692...Remote asset management = 1
21:24:03.694...Remote registry service state = 4
21:24:03.857...WMI service state (unless firewalled) = 1
21:24:04.051...Starting enumeration
21:24:04.059......Error: getting physcial monitor array (0x00000490) = Element not found
21:24:04.067......Error: getting physcial monitor array (0x00000490) = Element not found
21:24:04.076......Status = 00000000
21:24:04.079...Ending enumeration
21:24:04.102...Video power down timeout = 600
21:24:04.107...Display powered ON
21:24:04.109...User session connect
21:24:09.157...Refreshing screen object
21:31:12.144......Error: getting physcial monitor array (0x00000490) = Element not found
21:31:12.149......Error: getting physcial monitor array (0x00000490) = Element not found
21:31:13.178......Error: getting physcial monitor array (0x00000490) = Element not found
21:31:13.183......Error: getting physcial monitor array (0x00000490) = Element not found
21:31:24.931...\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
21:31:24.932...Dump: complete Windows device enumeration
21:31:24.934...1.DeviceName = \\.\DISPLAY1
21:31:24.936.....DeviceFlags = 00000005
21:31:24.937.....DeviceString = Intel(R) UHD Graphics 620
21:31:24.939.....DeviceID = PCI\VEN_8086&DEV_5917&SUBSYS_07E61028&REV_07
21:31:24.940.....DeviceKey = \Registry\Machine\System\CurrentControlSet\Control\Video\{EB346221-E0D8-11E9-8905-E3EC407063B6}\0000
21:31:24.944...2.DeviceName = \\.\DISPLAY2
21:31:24.945.....DeviceFlags = 00000000
21:31:24.946.....DeviceString = Intel(R) UHD Graphics 620
21:31:24.948.....DeviceID = PCI\VEN_8086&DEV_5917&SUBSYS_07E61028&REV_07
21:31:24.949.....DeviceKey = \Registry\Machine\System\CurrentControlSet\Control\Video\{EB346221-E0D8-11E9-8905-E3EC407063B6}\0001
21:31:24.953...3.DeviceName = \\.\DISPLAY3
21:31:24.954.....DeviceFlags = 00000000
21:31:24.956.....DeviceString = Intel(R) UHD Graphics 620
21:31:24.959.....DeviceID = PCI\VEN_8086&DEV_5917&SUBSYS_07E61028&REV_07
21:31:24.962.....DeviceKey = \Registry\Machine\System\CurrentControlSet\Control\Video\{EB346221-E0D8-11E9-8905-E3EC407063B6}\0002
21:31:24.967...Total number of monitors enumerated = 0
21:31:24.969...\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\

DDM1986 Diagnostic Log (uninstalled 1995 and installed 1986 to see if it would work to no avail):

Diagnostic Report, generated 19-May-20 (10.0.18363)
Copyright (c) 1995-2019, EnTech Taiwan.
Version = 1.50.0.1986
OS = 10.0.18363.2 x64
Mechanism = 3
Account = Standard
Command line = "C:\Program Files (x86)\Dell\Dell Display Manager\ddm.exe"
////////////////////////////////////////
AutoRestoreWindowLayout = 0x00000000
EnumErrorCount = 0x00000000
HintShown = 0x00000001
////////////////////////////////////////
21:58:52.720...Log opened
21:58:52.831...LanguageID = 00000409 00000409 00000409
21:58:52.843...Build = 1.50.0.1986
21:58:52.845...Thunderbolt driver = tbt100x 17.4.79.11
21:58:52.845...Windows handles = 00020180 0001011A 00010188
21:58:52.846...OS monitor sleep timeout value = 600 ms.
21:58:52.847...Applied DPI = 96-106
21:58:52.848...VM = 0
21:58:52.848...Registered DDM popup hotkey = Shift+Ctrl+D 6044
21:58:52.849...Registered EA layout MRU hotkey = Shift+Ctrl+Home 6024
21:58:52.850...Registered application window hotkey = Shift+Ctrl+Ins 602D
21:58:52.855...Remote asset management = 1
21:58:52.856...Remote registry service state = 4
21:58:52.955...WMI service state (unless firewalled) = 1
21:58:53.184...Starting enumeration
21:58:53.190......Error: getting physcial monitor array (0x00000490) = Element not found
21:58:53.195......Error: getting physcial monitor array (0x00000490) = Element not found
21:58:53.202......Status = 00000000
21:58:53.203...Ending enumeration
21:58:53.237...Video power down timeout = 600
21:58:53.238...User session connect
21:58:53.239...Display powered ON
21:58:58.247...Refreshing screen object
22:03:20.690...User session disconnect
22:03:23.848...Display powered OFF
22:25:37.880...User session connect
22:25:38.151...Display powered ON
22:25:45.660...Refreshing screen object
22:26:46.000...\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
22:26:46.000...Dump: complete Windows device enumeration
22:26:46.002...1.DeviceName = \\.\DISPLAY1
22:26:46.003.....DeviceFlags = 00000005
22:26:46.004.....DeviceString = Intel(R) UHD Graphics 620
22:26:46.005.....DeviceID = PCI\VEN_8086&DEV_5917&SUBSYS_07E61028&REV_07
22:26:46.006.....DeviceKey = \Registry\Machine\System\CurrentControlSet\Control\Video\{EB346221-E0D8-11E9-8905-E3EC407063B6}\0000
22:26:46.010...2.DeviceName = \\.\DISPLAY2
22:26:46.011.....DeviceFlags = 00000000
22:26:46.011.....DeviceString = Intel(R) UHD Graphics 620
22:26:46.011.....DeviceID = PCI\VEN_8086&DEV_5917&SUBSYS_07E61028&REV_07
22:26:46.012.....DeviceKey = \Registry\Machine\System\CurrentControlSet\Control\Video\{EB346221-E0D8-11E9-8905-E3EC407063B6}\0001
22:26:46.015...3.DeviceName = \\.\DISPLAY3
22:26:46.015.....DeviceFlags = 00000000
22:26:46.015.....DeviceString = Intel(R) UHD Graphics 620
22:26:46.016.....DeviceID = PCI\VEN_8086&DEV_5917&SUBSYS_07E61028&REV_07
22:26:46.016.....DeviceKey = \Registry\Machine\System\CurrentControlSet\Control\Video\{EB346221-E0D8-11E9-8905-E3EC407063B6}\0002
22:26:46.020...Total number of monitors enumerated = 0
22:26:46.021...\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\

Many thanks in advance.