[TPO]听力13的一句话不理解，请求翻译

BobbieZZUID: 2756583

【TPO】13听力第二个conversation
No problem, we've got a lot of rooms open right now. When you come in, you
sign your name on the list and I signed the room number or if you call that
event that it attended tell you your room number, if you forget, just come in and
take a look at the list. The videos are over there.


if you call that event that it attended tell you your room number
这句话请问怎么理解呢？

stillinheartUID: 2961704

Or if you call in advance then the attendant will tell you your room number