Recently our dryer (which is about 8 years old) has stopped drying our
clothes & I can't figure out why.

I've checked that nothing is blocking the vent outside and I've
detached the vent hose from the back to make sure that it is free of
debris. My wife cleans the filter every time she uses it and the
dryer is getting hot. It dries the clothes eventually, but it usually
takes 2 times (about 2 hours per load).

Anyone have any idea what I've missed or what could be causing it to
not dry?

thanks in advance
SpaceCap