Yep, MicroG has been installed while ago from Apps Store for sure.
Maybe an update of MicroG via Apps Store is available? There has been some big changes in the near past.
Just for documentation: I updated my FP3 (not rooted, locked bootloader). The only problem I found: The DB Navigator App didn’t start any more. I installed it again and now it works (lost of data inclusice 
).
Can you please add which build you came from? And: Pie or Q? Thanks!
Do you want to know the last build I came from (probably) or the original zip I started with on FP3?
Last thing I can tell you as the zip is still on my pc. Where can I find the the last build on the FP now (I did not note it)?