Same here - it's a "simple" problem - but I think only Enpass can solve it:
I have my WebDAV server with "Digest-Authentication" and running fine since a long time with Enpass. All updates ran without problems including 6.8.1. But on a new Mac (latest 12.4 / Intel), when adding a WebDAV account Enpass wants to authenticate with "Basic-Authentication" only.... switching to "Basic" on the server works for the new client, but you get the authentication error on the other clients which ran fine with "Digest" since the first setup.
So.... switched back to "Digest" and waiting for a fix or workaround.