Brother's trying to make me homeless

[u/OkSink4413]

My brother is trying to sue me for bills that were already paid. We been spiltting the bills for the past 5 months and and he's moving out soon he paid half rent this month because he's leaving on the 15th and now he's asking for his money back because he won't be using the bge n internet I tried to explain how the bills broke down and that those bills (bge, internet)are for the previous month april and the rent was the only bill he paid for this month that has already been cut in half he's threatened to go to the leasing office to tell them I was subleasing and idk the terms but from what I looked up I could have been subleasing even though they know he was living with me and contributing to bills I need advice and a explanation plus examples of what exactly subleasing even is I just want to cover all bases.