Wyoming Mineral rights

My family has a small lease in this section and we know of two producing wells. Mineral rights had been passed down through the family. Chesapeake is only paying on production of 100.00 or more per month. We are getting a check every other month. Yesterday, we were offered 4000.00 per acre to sell. I can’t figure out why. Any ideas?

Section 6 33 North 70 West