Phone screen is lifted up

@shoukathussain your image does not how. you want to try and repost it Adding images to an existing question

Most common issue with a lifted screen is a swelling battery that pushes against the display while expanding. Open your phone and check the battery. If it is swelling then you want to stop using you phone and replacing the battery as soon as you can.

If it is not the battery then it is possible that this is related to the display self de-laminating where the internal glue has failed and the screen separates. In that case replace the screen. Since iFixit does not yet have a guide for this, Use something like this video Replacement display are still available at many online stores. Purchase form a vendor that appeals to you.

While you work on your phone, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person that has the same problem as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.

Repair is War on Entropy!