What does it mean?

is there a way to automatically unignore?

this IP gets ignored in this torrent and it will be ignored in every torrent even if its working ok in others...

one must keep unignoring it, its a bit tedious... isn't it?

aside from this Tixati rocks, just great, I love it!

Upon completing the piece or after hashing data.. Tixati decided that peer sent bad data.
Therefore it keeps it from sending more without user intervention. This is possibly a transient condition. It is also possible the peer is malicious. You have the option to UNIGNORE or not.