Instagram complaint: Hacked account @mikkokookoo

My IG account @mikkokookoo was hacked on Sunday 22nd of May and the hacker changed my profile name to @_mikkokookoo__
Although I replied to IG emails about someone changing both my email address and phone number to something else immedtately – the hacker managed to go forward to it! Since then IG Help Center replies to my Hacked Account emails have all been very anonymous making me feel no-one has actually read them!
Also the video-selfie service to prove you are the owner of your account – it never works! I have sent numerous vide-selfies to them and always get the same reply: we do not recognise you, you can send another selfie later.
Also the links they send to get my account back never get me through to the the logging in process!
Very frustrating and bad service Instagram Help Center have! I have got all the proof and documents needed and stil they make it difficult for me to get my account @mikkokookoo back!
Attaching a photo of my page that the hacker has changed into @_mikkokookoo__