Me and my ex husband had set up an arrangement of the days he has our son its been going good for about 1 yr now but recently he called me to tell me the new arrangement he wants and he will be picking up our 2 year old on those days he wants without me agreeing he didn’t pick him up on his Sundays like he usually does because if what he wants, what can I do.?

*I dont agree because this is the 5th time hes wanted to change the schedule with our son I dont agree because its very unstable for him. (He gets every Sun-Mon with him and ai recently added 1 Saturday a month) that he agreed to until this week he doesnt agree anymore.