No prior test done for complaint

I contacted the above Electricians for a problem I have at my gate motor, as everytime it rains the Earth Leakage trips, I was told it was the joining connection and needed an Isolator, I agreed to pay the amount of R980.00 for this so called solution. (Which I paid). Last night we had a storm and this Isolator tripped the Earth Leakage again, on contacting AAA again this morning, they did come out only to tell me it's not there Isolator now It's the cable feeding the motor, Why only now is this the problem? Although according to \Wimpie"it will cost me an additional R1800.00"