Thanks for writing in.
Both Propranolol and Metoprolol belong to the class of antihypertensives known as beta blockers so it is ok to switch from one to the other. While Propranolol is a non selective beta blocker, Metoprolol is a selective blocker and is specifically used for high BP.
Metprolol will help control the BP better. Please get your BP checked regularly to make sure t is always under control. Take care!