I have been through Community user rejecting suggested edits either.
It seems most of the rejection cases is because of editing conflicts. Maybe the OP had had the edit button activated the time you did the action.
See the following thread on Meta Stack Overflow for more information on this matter:
How do suggested edits work?
I will quote a relevant part of it:
Sometimes the Community user approves or rejects my edit. What does that mean?
The Community user will appear to approve or reject your edit when one of the following two cases apply:
You submit a suggested edit at the same time as the original poster or a 2000+ rep user (20000+ in the case of tag wikis) or any moderator (in other words, anyone who has full edit privileges over the specific post). In that case, your suggested edit will be rejected by Community in favor of the fully privileged edit. Since the Community user does not provide a message when such an edit is rejected, it may appear as though the system has rejected your edit immediately, without warning. Don't worry! This has nothing to do with bans, or your profile being banned from suggesting edits. Just try submitting your edit again and it could make it to the review queue.
In any case, suggested edits rejected by Community are not counted towards the suggested edit ban.