I've had a similar experience. What make this into a bug and worse is the Android client supports IPv6 and you can save IPv6 entries, yet if you then try to edit those entries on the web, chrome or the macOS client, either of those clients won't allow you to save any updates without deleting the IPv6 entry added by the Android client. I'm told the this is a "feature" - it's very frustrating especially given the lack of empathy from the support and development teams on this issue. This is basic stuff.
I've had a similar experience. What make this into a bug and worse is the Android client supports IPv6 and you can save IPv6 entries, yet if you then try to edit those entries on the web, chrome or the macOS client, either of those clients won't allow you to save any updates without deleting the IPv6 entry added by the Android client. I'm told the this is a "feature" - it's very frustrating especially given the lack of empathy from the support and development teams on this issue. This is basic stuff.