If you have more than one jetway, and one of them can work at more than one exit, it's not possible for GSX to know if they will eventually cross, so you should't use the automatic servicing option there, and control jetways by yourself.
We usually prevent this to be happening in our sceneries, by carefully placing jetways in a way that, on the proper stop position, each jetway will only work on a single door, so the problem cannot happen there, but that might not always be the case on 3rd party sceneries.