1. The Trustee is not police to enforce law,
2. If some illegal activity has been found there, the matter should be reported to police,
3. Moreover, the said activities shall have to be clearly mentioned as illegal in IPC,
4. Drinking bear in own room is not illegal, even if the room has been taken on commertiasl purpose,
5. The trustee has taken the role of moral police,
6. You can take him to Court & get the relief but it may be a messy matter since he may also come out with evidence of objectionable activities in the said room which you may not know, since the key of the room was also with some other person,
7. Settle the matter with him amicably in your interest.