Borewell stuck - advice requested

We drilled a borewell in our farm about 3 months ago and went upto 450 ft. 3 inch water was struck. Installed 7.5 HP motor about 300 ft. Within a month the motor was stuck and we had to take it out. It was completely filled with sand. We cleaned it and then placed it at 240 level. Again within a month it got stuck and had to take it out. We found water level was at 30 ft and sand was there at 200 fwt level. This time we kept a 5 HP pump and placed it at 130 ft . Now water is pumping with a gap.

What is the solution to this issue? Please advise

Thanks

Why don’'t you install a casing pipe till 300 ft and place the motor at 240ft ?