Unable to sync via WebDav (even ver 1.20)

[divsys1]

A previously working WebDav setup is now failing after updating to Ver 1.19.
Devices will not sync and/or I cannot retrieve Backups via HTTP.

Details requested:

• device make / model
  Samsung Galaxy A51
• android version
  Android ver. 11, Kernel 4.14.113-22754548
• sync method (are you using "HTTP" sync method to access WebDAV server?)
  HTTP to a local IP address : "http://192.168.124.xxx:8887/userid".
  No Username/Password is required. There is no direct outside access, I have setup OpenVPN to allow "roaming" sync's.
• any error messages you're receiving
  When I try to Sync or Download Remote Database, I get: "Problem Downloading Database"

[divsys1]

Updated to ver 1.20, still no change.