CompatabilityLevel is very rarely the issue. (maybe it is for you, but it is rare).
Is your database actually called cm_PS1? or was that just the query you found, and presumed that everyone's CM database is cm_ps1 (it may not be, for you)?
If your DB is called cm_ps1...then that result for alter database means you don't have rights to do that on that DB. (which is odd, since you were able to change legacycardinality). Based on what you posted, your DB is actually cm_ew0 ?
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I suggest you do this... if you haven't already done so. Basically, if you are not already doing the Ola Hollangren routine... you are missing out, and desperately need that set up, yesterday if not sooner than yesterday!
https://msendpointmgr.com/2017/01/03/configuration-manager-sql-database-maintenance/
and (possibly / probably / maybe) this:
https://emptygarden.info/2018/03/the-very-best-configmgr-database-maintenance-plan-in-the-entire-world/