MetOpera contribution header printed on a subscription order?

Hello everyone!

My team is in the process of printing our subscriptions prior to mailing.  We are doing this manually, and we had an unusual header print while we were doing this.  This header printed on only one order about 100 or so orders in, and it was for both an actual order and constituent. I have no clue where this design came from.  Has anyone else experienced this?  It says METOPERA on it, so I assume its a template of some kind, but I thought it was super strange that it only happened to one order. When I tried reprinting the header, it was totally normal.

My mind is mildly blown trying to figure out what caused this.  Any ideas Tessitura hive-mind?

Thanks!