avisamelo is incorrectly written, and should be written as "Let me know what" being its meaning:
2nd person singular imperative of the verb to warn whenever there are what tell, tell, warn someone of something, notify, prevent, apercibir, communicate, advise, announce, inform. The challenge usually bring enclitic personal pronouns; in this case I, first person, exerting indirect complement and, third person, exercising direct plug-in, which makes the word sobreesdrujula, let me know it, although the cone South America I think they consider it esdrujula: avisamelo.
