I have wheel barrel with a deflated tire and it is to the point that it
is loose on the rim bit it is not punctured. It is relatively new and
has always lost air periodically. Someone told me the bead? is not
great on those tires and best option is to add a tube. Should I buy a
new tire, am I able to reseal the existing tire, or is my best option
to add a tube?

Much appreciated in advance