Hi,
You need to go to the master socket, the first one in from the external cable, which should be a large socket with a vertical split 2/3 rds of the way down it, you undo the two small screws, then pull out the lower faceplate, which would have your extension wires connected to it, so do it gently and let it hand down on the wires, then if you look inside the socket that is still remaining, on the right hand side there will be another inlet for a phone plug. plug your phone into that and ring it, if it still trips after one or two rings then the fault is either " ring tripping" a fault that BT will cure, or possibly your phone, so try another, and eliminate the phone from the equation. if you do not ring trip in the test point in the master socket, then the fault is within your property. have a look at the small faceplate that you removed at first, and any wires connected to anything other than terminals 2 and 5 should be removed, then replace the faceplate and try again, but normally ring trip is a BT fault, just make sure that the cable feeding the master socket has not been damaged anywhere, because if BT come out and find the fault has been caused by you or your gardener etc. then they charge £150 plus VAT for the first 45 mins, then £90 per hour after that.