sounds like a contactor fault the contactors are double sided when one contactor operates the other contactor is closed and relies on the tip on the back of it to make a circuit so if it is not sitting correctly you will get that problem i have also found in he past that the reason for this is the bottom of the contactor assembly
where it pivots wears and doesnt sit properly solution is to change the contactor assembly they come as a pair hope this helps good luck