Unable to receive messages

[BBurkhardt]

Bevor you create a new issue:

- [x ] I searched for similar issues and did not find one
- [x ] I'm using the latest version available in the [Windows Store](https://www.microsoft.com/store/apps/9NW16X9JB5WV)

I'm submitting a...:

• Bug report (I searched for similar issues and did not find one)

Current behavior:

I'm unable to receive messages in the desktop client. Outgoing messages are fine and I receive replys from my contacts in my Android XMPP client (Conversations). This occurs with OMEMO-encrypted messages as well as non-encrypted ones.
(Me and my contacts have an accounts on jabber.de)

Expected behavior:

Receiving Messages

Minimal reproduction of the problem with instructions:

There's not much I can say, I just installed the App and tried to use it with contacts with whom I previously chatted with using Gajim.

Environment:

App Version(s): 
v.0.30.0.0 <!-- Which version of the App are you using (e.g. v.0.2.0) -->

Windows 10 Version Number: <!-- https://en.wikipedia.org/wiki/Windows_10_version_history -->
- [x] 20H2
- [ ] 1809
- [ ] 1803
- [ ] 1709
- [ ] 1703
- [ ] 1607
- [ ] 1511
- [ ] 1507
- [ ] Insider Build (build number: )
- [ ] Misc:

Device form factor:
- [x ] Desktop
- [ ] Mobile
- [ ] Xbox
- [ ] Surface Hub

Where did you got the APP from?
- [x ] [Windows Store](https://www.microsoft.com/store/apps/9NW16X9JB5WV)
- [ ] Self-build, using a provided release source
- [ ] Self-build, repo cloned at [dd.mm.yyy] <!-- When did you clone the repo! -->
- [ ] Misc, got it from... <!-- Please tell us your source! -->

[COM8]

Correct me, in case I'm wrong:

• Sending works. Send messages appear in UWPX and in Conversations.
• Receiving is broken. You only receive them in Conversations.

[BBurkhardt]

That's the observed behavior, exactly.

[COM8]

Perhaps this might be a MAM issue in combination with CC.

[COM8]

I will have a look at it as soon as #146 is done since this PR changes a lot of stuff in the background.

[COM8]

Does this bug still exist with the latest release of UWPX, since I refactored the way MAM works?