New Owner - Missing pass and Username

hi dear 

its vahid new owner diamond hostel

I buy this hostel . but last owner(Ali) dont give back to me pass and usname about hostel , but I payd all tax booking , and after call to office booking about payment and plz help me becuse i dont had sim card .plz tell me what we can do for this problem . 

this my number +995 555 11 79 74