iphone xr is sim lock - request to unlock

HI , i had iPhone xr 128 Gb i bought it  from someone else and i am  used    almost two years back , 

 recently i bough new phone  i removed the sim and i inserted new sim ,  is pop the  primary carrier but i selected wrong and i did many times,  untill sim is lock,  

 HERE  IS THE IMEI NUMBER:  357331090270412

HOW CAN  YOU HELP ME TO UNLOCK ?  THERE IS ANY CHARGES?  IM AM FROM  DUBAI,UAE .