Good for approximately two weeks, it is impossible to receive calls on my telephone line, when calling from any number to my line it sounds busy, all the phones are well hung and if they have a tone, calls can be made but not received, being off-hook and Calling the line sounds busy but slower, and when it is ringing it sounds faster, I have tried to disconnect all the phones and still keep busy when calling, when measuring in telephone sockets I have 49vdc hung, 9v off hook, and 107vac hung and 99vac off-hook, when calling while at 107vac, it goes down quickly to 99vac and goes back up to 107vac, can you help me?

I am from Venezuela, could the internal wiring give this fault?