Go to Google play store settings, right down the bottom it will say device certified or not. If it's not certified that's your problem.I have a Samsung Tab S2 that I previously had Lineage OS 16 and recently installed an unofficial Lineage OS 17.1 rom. I got everything working but Netflix and Disney Plus are not showing up in the Google Play Store. So I installed Magisk and MagiskHide Props Config. After a reboot I now pass a Safety Net check.
1. The previously mentioned apps still don't show in the Google Play Store.
2. I read something about keeping your device certified by installing a configuration file. It says to do it before setting up your device but I already have everything setup. Can I still do it or will I have to clean install and start over?
With stock LOS I didn't have this issue but with this custom rom I am.
Go to phone settings > apps > google play store and delete cache and data
Wait a few minutes then open play store and it should say certified, and the apps should be available for download