Most often when any dryer is taking longer to dry it is because of a air flow problem.
I would check the dryer vent first to make sure it's lint free and has no kinks in it.
If the vent checks out ok I would then look at the blower housing inside the dryer and remove the lint build up from the housing and blower fan.
Even if you feel that the dryer exhaust seems like it's blowing good the lint build up inside the dryer housing around the fan/blower housing can still increase the drying time.