Hello Doctor, In My Wife Case She Has Already Given

Hello doctor, in my wife case she has already given birth one time our son is now 3 years old , but now as of now even after planning a lot she is unable to conceive , later after diagnosing we found that Endo level is 5.5 , and she has been recommended to take duphantson tablet for 3 weeks but still no improvement , can you please suggest what do we do next or is it time to give up the hope.
Is Endo result of 5.5 a bad result.