Borewell casing pressed and submersible pump stuck at 55ft in Hyderabad, Andhra Pradesh

I have a problem with my borewell located in Hyderabad, Attapur, Near Mehidipatnam. where the casing of the borewell is internally pressed at 55th feet. The borewell is with 6 and ½ inches in diameter, depth of the borewell is 550 feet, casing is used till 60 - 70 feet (type unknown).
The casing pipe at the depth of 55 feet, both the edjes of the casing came closer that is they are internally pressed together by which the diameter is reduced from 6 ½ inches to 2 ½ inches. On lowering the submersible pump it will not go down further than 55ft.

Kindly advice as to what remedies I can apply.

Racharla Sampath Kumar