Had this problem on our 26 and a ford 150. After talking to my master electrician friend, he said clean out the dielectric grease with brake cleaner and connect again. Success.
to quote a source....Ensure that the grease does not touch the path of electrical currents or where parts are connecting. This is because the grease is an insulator, and it disrupts the flow of currents. Therefore, it is recommended to use dielectric grease on surfaces of electrical parts where the currents are not passing.
here is that source... https://rxmechanic.com/what-is-dielectric-grease/
I know this will probably start a fight...