MicroG vs. Google Play Services

[kaari]

I think prefered FakeStore to install is this:

Release v0.1.0 · microg/FakeStore

not from F-Droid. with that I got it working,
As mentioned here:

[4.5.0.16] Signal Android with MicroG complains about not being able to register with play services

How did you install it? From F-Droid? If so, locate “FakeStore” in F-Droid, scroll down to “Versions” and select version 0.1.0, by default 0.0.2 gets installed. If you installed it from somewhere else, make sure to install version 0.1.0 of FakeStore by whatever means.