None of the Venue 8 Pro's charge reliably. It's a known issue with this device and Dell knows about it and refuses to acknowledge it. You can plug the charger in, turn it upside down, disconnect it from the device and plug it in again, say some voodoo on top of it, and it might charge and it might not. I was once very much a fan of Dell products, after the Venue 8 Pro experience, I'll never own another Dell and I'll advise my friends that they sell junk.

Did you try a different charger and/or USB cable attached to the charger?  Is there any issue with the port on the tablet that you plug the charger cable into?  Can you provide any particulars as to how/when this came about?

There are two possibilities that come to mind off the top of my head.

1. The micro USB connector was forced into the tablet upside down, possibility breaking the USB port.

2. You are not using the supplied power supply.  The Dell power supply shorts the USB data lines which tells he tablet that it is connected to a high current power supply.  A generic power supply doesn't have this short and will not work unless you buy or modify a USB cable with the data wires shorted.

Hi Jeff,

would you suggest I book it in?

There is a possibility that your micro USB connector has been damaged. The Dell micro USB is a female connector and it is RECTANGULAR. The charging micro USB male connector has "somewhat" curved/slanted sides. Take a close look and you have to figure that out. For that problem, check out ebay for Dell Venue 8 Pro micro USB repair solutions for out of warranty unit.

I had the same problem before, however, my micro USB charging cable has worn out. A new cable replacement was the solution. Good luck!

What does "book it in" mean?

You really need to explain the situation further. 

Are you using the original Dell charger?  If not, can you switch back to it, and does that fix matters?  Are the metal pins in the port that the charger plugs into bent, so that they won't fit into the charger's plug?

should i send it to dell for a check?

What Mikerman said.

None of the Venue 8 Pro's charge reliably. It's a known issue with this device and Dell knows about it and refuses to acknowledge it. You can plug the charger in, turn it upside down, disconnect it from the device and plug it in again, say some voodoo on top of it, and it might charge and it might not. I was once very much a fan of Dell products, after the Venue 8 Pro experience, I'll never own another Dell and I'll advise my friends that they sell junk.

I've had my Venue 8 Pro for over 2 1/2 years and NEVER have had a charge problem.