Legal consequences for non-payment of Etisalat bills

I have a flatmate who applied for internet in Etisalat, but when he went on vacation he did not come back. Then our flat owner continued it but the internet account was not transferred to his name.

When I got back from my vacation, there was already a new flat owner. She removed the existing internet in our home because she applied for a new account. That was almost 2 years ago.

Now, I don't know why Etisalat is texting and calling me that I have to pay the amount due and they initiated a legal action and travel ban on me. Tahseel messaged me about this.

Please, can anyone help me on what I can do?