Am I Supposed To Pay Rent Again?

My landlord and I have been doing something for three months now. He's a young vibrant guy. 

His dad gave him the house but he's a hard working man too. So we have been into each other deeply. 

My rent expired last month and he did not raise the issue. But on Wednesday I receive a written message from a lawyer about quitting the premises if I can't afford the rent. I was shocked because am dating the landlord why paying rent? 

I waited for him to come back and I even called him to tell him about the message I received. He said he's driving home. Getting home I showed him the message he said that's how lawyers do. That once a property is left under their care whether the person is the landlord’s daughter or wife that the next thing he will apply force to make sure I pay. I told him I don't understand, besides the first year I paid it was paid directly to the landlord not to a lawyer. How come a lawyer is issuing me notice now? He said that's how lawyers do once an apartment is placed under their care. 

This guy since we started seeing has only given me 50,000 though he takes me out. The rent has also increased from 120k to 180k. Where do I start from? He said there's nothing he can do about it , I told him to call the lawyer, he called him in my presence and the lawyer said he's only doing his job. Doing his job for who? My landlord's father is late he's the the one in charge of all the properties so who is the lawyer doing his job for? I have been given up till next month ending to move out or I make payment directly to the lawyer. 

Is this even right? I am his girlfriend. We are sleeping together. Since we started I haven't slept in my room. I sleep in his room, I cook there and do everything there why should I pay rent for my apartment again? I told him if that's the case I should move in with him he said his sisters do visit and the room we have been sleeping even belongs to her. But we are inti*mate and always into each other. I also believe he loves me because he gave me that 50,000 Naira to add to my business when he was also looking for money to do something. So it's not about him not loving me. What could be the problem please? 

Help me post. 

We are still doing things together, and he's trying to let the lawyer understand that I am his woman but the lawyer kept saying he can't do his job for him. 

My man is the eldest son so what is this lawyer even saying? Since we started dating I haven't really been saving for my rent because I thought there would be no need. Is this how lawyers do their job? 

Please I need advice and opinions.