Town an country heat and temp issue

So I am having an issue with my wife’s town
an country. The heat will work in the front fine
for a little while but it will start to go cold an
then if I accelerate hard and get high rpms
the heat will come back. It will also
sometimes get back hot after I turn the heat
off for a few then turn it back on again. The
second issue is the rear a/c if I turn the heat
on in the rear and select face it will blow ice
cold no matter how long I leave it on but if I
switch it to feet it blows hot. Lastly with any
of this the temp on the vehicle will rise from
the half way mark to the three quarter mark, it
normally doesn’t go over that but it has been
really cold lately. Any help on what to
do/replace would be much appreciated.