I have a connection from xendesk to jira cloud, some tickets are synchronized, not the newest ones. 
the sync queu of both ends show different values. 

Jira side: Outgoing sync (135) Incoming sync (48) Outgoing attachments (0) Incoming attachments (0). 
Xen-side: Outgoing sync (765) Incoming sync (64) Outgoing attachments (72) Incoming attachments (0). 

I tried to do the clean-up but without any error message it tells me that it may take a few minutes and it never cleans these pending.
Already synced issues works great.

Can it be possible that this cleaning action, until it is completed, prevents the exalation of new tickets?