Memory upgrade Dell 3891

I have a Dell 3891 which I purchased in Aug. 2021. Intel i7, 8 GB ram, 512 solid state drive, CDROM.  I wanted to upgrade to 16 GB ram, so ordered an 8GB stick from Dell in November. Due to health issues, I just this past week attempted to install the stick in the PC.  After installing in the empty RAM slot, the PC failed to power up,  I performed the CMOS reset by removing the coin battery as instructed in the manual. Still no power up. I then removed the new stick. Still no power up. Then repeated the CMOS reset, finally getting it to power up but only with the original 8 GB ram. 

This was the upgrade RAM I purchased: Dell Memory Upgrade - 8GB - 1Rx16 DDR4 UDIMM 3200 MT/s .  

I have not upgraded the BIOS.  What could be the problem? Is this replacement RAM not compatible with this PC, even thought the Dell website said it was?
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