B737 Captain reported the aircraft rolled uncommanded during pushback when the brakes were released. Captain applied brakes to stop aircraft.

Narrative

We were pushing off gate XX at ZZZ. We were instructed to push tail north. The push went uneventfully. The push man was in the process of disconnecting when ramp advised that we need to push deeper and that we were in the wrong place. I caught the push man and relayed this to him. He did not seem to understand and neither did I because we had complied with push instructions. The ramp then told us we were on the wrong line which didn't make sense since we were clearly on the X line. They advised us to tell the push crew to comply with a 'full' push. The push man was confused by what 'full' was because what we did seemed pretty normal. He agreed to try to push us deeper. I coordinated brake release with him to push again. When I released the brakes we rolled about a foot and he told me to stop. I reapplied the brakes. The ramp controller was insistent that we comply with his instructions but they really didn't make sense. Finally the push man told me there was an aircraft behind us and we could not go any deeper. At this point the ramp controller told us to just disconnect where we were and execute a 180 to go out the North port. In this confusion we had coordinated braked release but apparently we were not captured by the tug. This entire exchange was very confusing for everyone.