Recently upgraded Nextcloudpi to 13, now I can't log in

POST TITLE EDITED TO NEW ISSUE DESCRIBED IN REPLY COMMENT

Nextcloud version (eg, 12.0.2): 13.0.1
Operating system and version (eg, Ubuntu 17.04): Raspian
Apache or nginx version (eg, Apache 2.4.25): 2.4.25
PHP version (eg, 7.1): 7
NextCloudPlus Version: v0.56.16

The issue you are facing:
Everything was working yesterday after an update from 12 to 13 and today i try to login and nothing happens. The sd i’m using has recently been restored from a backup image i made from few weeks ago (previous sd became corrupted). I’m considering nc-init but i want to check what i would lose? Could I just add the same users back and everything would still be as it was as far as files that are stored on the hdd for each user?

Is this the first time you’ve seen this error? (Y/N): y

Update: Login page is unavailable now (HTTP Error 500) and nc-info is reporting MariaDB is down

output of sudo ncp-report?

I think a ropey power supply was causing an issue. I rolled back to a backup and the same thing happened after two days. Rolled back again then replaced the power supply and all is well.

I do have another minor problem that has recently cropped up though. I’m using the desktop sync client on my laptop (Ubuntu 16.06) all works well until my VPN app disconnects. I then get a connection refused error. I am using dnsmasq which works fine with other connections on my network (android phones/tablets etc). It’s not a huge deal but as it previously worked fine I know there must be a solution! Any suggestions?