rappelle vs. rappelles

Question

In the lesson i wrote Tu me RAPELLE ta mere; but the correct answer is given as RAPELLES, which seems like a plural

Accepted Answer

I presume it was actually "rappelles" not 'rapelles' given as the correct answer ? 
It is just the normal conjugation of verbs with 'tu' - apart from a few exceptions that end in 'x' (eg veux, peux), and in the dropping of the 's' in the imperative conjugation of '-er', '-frir' and '-vrir' verbs (unless followed by 'en' or 'y', when the 's' is retained) - all simple tense conjugations of verbs with 'tu' end in 's'. Nothing to do with plural, as 'tu' is always singular.

Answer

Bonjour Tony,
See link below for the conjugation of rappeler: 
conjugate-eter-and-eler-verbs-in-le-present
I hope this is helpful.
Bonne journée !