Facebook hacked

Hello
My wife used a sim earlier and that mobile no was feed up in facebook ac..after that she stopped using the sim but number was left on facebook...some hacker got that number and hacked the facebook by getting the otp and had changed password and email...now she cant access to her mail and she dont have earlier mobile no..so its not possible to get otp and regain her facebook... That hacker is posting communal words using our photos..i want to recover my wifes account facebook. Plz help me