My house was built 11 years ago. I have two bathrooms upstairs. In my master bath, it takes more than 20 minutes to fill the tub with hot water. The pressure is extremely low. When I turn the water to cold the pressure is strong.

In the other full bath upstairs, I have equal strong pressure when filling the tub using both hot and cold water.

What can be the issue in in the master bath, and what can I do to fix it?