Temporary hit points do not prevent you from recovering regular hit points
The section on "Hit Points" under "Damage and Healing" states:
[...] A creature's current hit points (usually just called hit points) can be any number from the creature's hit point maximum down to 0. This number changes frequently as a creature takes damage or receives healing [...]
And then the section on "Temporary Hit Points" states:
Some spells and special abilities confer temporary hit points to a creature. Temporary hit points aren't actual hit points; they are a buffer against damage, a pool of hit points that protect you from injury [...]
Nowhere in the section does it say that you cannot be healed while having temporary hit points. In fact, they are defined as a buffer against damage, and all of their effects and how they work regarding damage are defined. If they were meant to prevent you from being healed this would be stated. Also note that the section on hit points never states that you are prevented from receiving healing while you have temporary hit points.
Because nothing in the text and rules states or even alludes to temporary hit points preventing you from receiving normal healing, they do not prevent this.