My boyfriend dont understand me and its causing a problem????????

Lately when we're on the phone and I ask him stuff or say stuff to him he dont answer and he lives with his cousin right now and she's always in the background talking and laughing with him and it gets on my nerves he act like he cant never just say Im on the phone the other day he even cut me of while I was talking to spend a hour laughing and talking to her and I just been feeling like he's ignoring me but everytime I tell him about he shuts me down like im not ignoring you you need to stop saying that and im tired of complaining about the samething he just dont get it any advice ? What could I do or say to make him understand where im coming from ?