Lucky Patcher broke my Google Play services

I have a OnePlus 6 running Android 9.0.2 rooted with Magisk, but no recovery. (I tried to install recovery before rooting it every way I could imagine, with no success.)

I had Lucky Patcher installed with patches applied to Android and to the Play Store, and everything was working fine. I recently updated Android from 8.1 to 9.0.2 and the patches were removed.

When I tried to patch it again, the play store disappeared and all the Google apps say that my device doesn't support Google Play Services.

I tried reinstalling the Play Store both from Lucky Patcher (original and mod versions) and from APKMirror, but whenever I try to open the app, it just says "Google Play Store keeps stopping".

And when I tried installing the Play Store as a system app with Lucky Patcher, it just wouldn't install.

I tried installing Google Play services from APKMirror, but the app just wouldn't install.

I even tried installing it using ADB, and I get this error:

Failed to install Downloads/ps.apk: 

Failure [INSTALL_FAILED_UPDATE_INCOMPATIBLE: 

Update to package com.google.android.gms doesn't support multi arch]

My question is, how can I get the Play Store and Google Play Services working again?