Battery not detected issue

Hello there!

My local computer store let my swap the old and defunct battery in my Dell Latitude e6420 for a brand new one, but windows 10 doesn't detect the new battery. When I plug in my charger the battery light on my laptop alternates between flashing amber and a (not flashing) blue light. I have tried my best to troubleshoot this issue, I have tried to hard-rest the computer, I have uninstalled the Microsoft ACPI entries in Device Manager and I have shut the laptop down and removed the battery several times, but nothing has worked so far. I can't update the BIOS because the system doesn't detect the battery and without battery you can't update the BIOS. Is there anything else I can try?