by Joseph Whitelow
Use Google Pay with root after Play Services 15 update!
This script requires SQL from Magisk modules repo! Make sure to install it and reboot the device. Delete your G Pay cards and re-add them AFTER enabling script. If you can add the card - most likely, the payments will also work. But, I give no warranty, always have a credit card or cash. Also, download and run "Google Pay root fix 2019 - loop" script! These two scripts should run together.
This script runs in background and resets G Pay attestation databases and locks these at boot. This should allow to use G Pay with root.
The original author and thread of the method can be found on xda: https://forum.xda-developers.com/apps/magisk/magisk-google-pay-gms-17-1-22-pie-t3929950
So it's not completely my idea, I made a little bit reworking of commands and added some automation, so it is easy to install and use.
This works for me and many others, but I cannot give 100% warranty that it will work for you.