This annoying bug plagued Mi Note 3 on Android Oreo for quite a long time for some users. I think that it's now fixed on Pie. It's probably a bug in xiaomi sources itself. Report it there.
It's really weird because many Mi Note 3 users who have the 128gb model have problems that are not appearing on the 64gb model. I talk in general, not problems related to xiaomi.eu rom. Sorry for offtopic - but just to confirm your theory.
On 10.4.1 it's a known problem. I hoped that in 10.4.2 it would be fixed but that's not the case. Nevermind it's not eu rom problem but official China rom issue. We have to wait for the next update.
You are running xiaomi.eu rom or the official china rom? If you are using the first one flash the official rom with MiFlash and check if the problem persists. If everything is good flash recovery and eu rom again.
Look ate the download page of the stable/beta rom and there you will find a table with all supported devices with their respective codenames. Then go to the download page and by the codename you will find your rom.