To perform a reset go to System Backup and restore Reset network settings.
Install them choose version 9083430
Go to Settings Account then delete your Google account
Boot the phone into recovery model, and wipe the cache partition This process would take about 5-20 minutes
After wiping the cache, reboot the phone and add your Google account
A member,who shared this fix on the forum, claims that his battery drain has dropped dramatically and his battery statistics show the correct figure.
Encryption issue: Many users on OnePlus forum have reported that updating an encrypted device to Cyanogen OS 13 does not work.
Despite being correct, the pattern was rejected," states a user on CynogenMod jira site.
While it is possible to use adb sideload to install the previous the previous version, it's a bit technical and beyond many people's abilities.
To resolve this problem you might consider installing the previous Cynogen OS version 12.1 via ADB sideload.