Nonsense.

By "wall mounted" you mean the inside part of a mini-split system, yes?

From there, I may be able to help you find the drain tube and clear the blockage.
 

 Yeah it’s split between a unit inside and outside. I see what might be the hose for drainage, maybe check that first 

 If the inside can be accessed from the drip-pan, a thin wire or light air pressure can be used to clear the hose.