4.5yr old son so inconsistent using the toilet

[H84AA]

My son is 4.5yrs old. He is very inconsistent with using the toilet. Some days he can be dry all day and others has 3 or more accidents both wee and poo. He doesn't say he needs to go very often, but usually knows and says he has to when he has no bottoms on. It doesn't bother him if his pants are wet or dirty, we have tried reward charts, praise, treats, taking toys away etc and nothing seems to work. He is not constipated neither does he have an uti, any advice is really appreciated or if someone has dealt with this before what worked?

[Yaleamanda]

Do you encourage regular toilet sits after every meal? What do his stools look like on the Bristol Stool chart?

[H84AA]

Hi yes we do and his stools are normal, he goes daily or alternate days ranging from formed but soft and occasionally a littler softer.