Instead of the reason, there should be a link to the rules, something like this >

"Sorry (username), you are banned from posting or sending personal messages on this forum.
You have been banned by a forum moderator. Read the rules and you will find out what you were banned for. You may appeal here: banappeals-w6pquw43@theymos.e4ward.com""

That will make them read the rules and not abuse new account they open for appeal.