Lease cancellation question

I own mineral rights in Grady County, OK - sections 13 and 14. OKLAND appears to hold leases signed many years ago by my now-deceased Mother - I do not have copies of these leases. OKLAND continues to make VERY small royalty payments - i.e. in 2014 - $35.20; in 2015 - $24.11; in 2016 - $13.85; in 2017 - $7.11; in 2018 - $7.03. These are totals for wells on both sections 13 and 14.

How do I get this lease(s) cancelled so I can explore a new lease?

I receive phone/mail inquiries regularly from companies wanting to purchase my holdings for $8,000 plus per mineral acre - which leads me to think these may be valuable properties and that OKLAND may be continuing minimal payments either for active or inactive wells just to retain control. Could this line of thinking be accurate?

I will appreciate any input.

I understand that you cannot have a lease cancelled unless you go to court and can prove that the wells are uneconomic. Yes, they are trying to retain control.