Calendar events not uploading via CalDAV

For years, I’ve been using Exchange with ActiveSync, so now that I’m using Axigen, this is my first time using CardDAV & CalDAV. I was told that by Axigen that they suggest using DAVx5, which I have installed on my Android phone. While I can download appointments to the phone without a problem, I’ve noticed that if I add a new appointment into my phone, it does NOT upload it to the Axigen server. I don’t see anything in the logs and am wondering if it’s just a permissions issue (read vs. change) or if there is something else that I can look at.

Something I forgot to mention - CardDAV works fine - new contacts upload to Axigen without a problem. It’s only Calendar items that don’t. Anyone have any ideas?