There has been an update. As far as the reason for the call:

A league official told officers that parents were upset about their son’s playing time and that the child would no longer be allowed to participate in the league.

Another entry states that the parents were upset because they believed their child was being criticized for playing too well and was being taken out of the game.

So it sounds like the coach benched the kid at some point, maybe to give the other kids some time to kick the ball, and the parents argued with the coach about it, which led to them being refunded and asked to leave, which they refused to do until after police got there.

In a statement released Monday, the department said a league official requested police assistance with a disturbance between league officials and the parents.

The league had asked the family to leave and offered to refund its fees, according to the statement. After officers arrived, a league official asked them to speak with the family because he did not want to prolong the disturbance, police said.

The family told officers the game was over and they were leaving. Police described the family as cooperative and said officers provided an event number at the family’s request.

The department characterized the incident as a civil matter, not a criminal one. “No one was arrested, trespassed, or forced to leave the park,” the department said.

https://www.yahoo.com/news/articles/winter-park-police-explain-response-164621178.html