Dionaea said there was a bug in the (automated?) system they devised to track and ban the accounts that redeemed excessive tickets, so your 2 friends may have been hit by that. If that's the case, then a ticket to support should resolve the situation if it hasn't been already.
Support was contacted 3 days ago and still no answer for either player. Regardless thye still been unable to play for the last 3 days when they did nothing to break the tos.
If you do that sort of thing thats 3x dailies and mini's so 420 shells that they missed out on. If they lucky they may still have the daily reset tickets they purchased.
Really a simple sorry probably isn't enough for some players... but I dont see gameforge offering anything as remittance for their mistake.
Merry Xmas we banned your account by mistake, sorry bout that.... here's a cookie?