Files stopped syncing. When checked the web page, it turns out it is a forced update to version 15.0.2 as seen in the ss.

When clicked on to âstart updateâ, it results in error. The last repair step is to âextract the vcard uid and store it in the dbâ.

Then it puts itself into maintenance mode until I restart the snap, in which case it starts over from the âstart updateâ page. How to troubleshoot?
What I could find is that the line in the logs below that repair step is about memory limits.
{âreqIdâ:âXshGdYhMa5PsodOS2q3pâ,âlevelâ:1,âtimeâ:â2019-02-11T08:59:39+00:00â,âremoteAddrâ:ââ,âuserâ:âââ,âappâ:âupdaterâ,âmethodâ:ââ,âurlâ:âââ,âmessageâ:â\OC\Repair::step: Repair step: Extract the vcard uid and store it in the dbâ,âuserAgentâ:âââ,âversionâ:â14.0.6.0â}
{âreqIdâ:âXshGdYhMa5PsodOS2q3pâ,âlevelâ:3,âtimeâ:â2019-02-11T08:59:41+00:00â,âremoteAddrâ:ââ,âuserâ:âââ,âappâ:âPHPâ,âmethodâ:ââ,âurlâ:âââ,âmessageâ:âAllowed memory size of 134217728 bytes exhausted (tried to allocate 217088 bytes) at /snap/nextcloud/11343/htdocs/3rdparty/sabre/vobject/lib/Parser/MimeDir.php#319â,âuserAgentâ:âââ,âversionâ:â14.0.6.0â}
Also, it says âneedsDbUpgrade:trueâ in the nextcloud status. So maybe it is relevant.