Please advise what is it called when you are allergic to general anesthesia?

No such thing. There is no such thing as being allergic to general anesthesia. General anesthesia is a garbage can term for a mix of a ton of different medications that are used in anesthesia. If you have an allergy it is usually specific to one component that can be easily swapped out.
General anesthesia. Allergy to general anesthesia is called 'allergy to general anesthesia'. At times the reaction may be more specifically indentified as urticarial (hives) or anaphylactic (low blood pressure).