Guernsey Co. Ohio/ Gas/Oil lease

March 31st at Prichard Laughlin a group signed leases for $5.9K per acre with 20% royalty. 120 days till payment was due. In August or September we signed a certified letter extending the date for pyments 30 more days. Have cashed a check for about $200 from Turner oil out of Oklahoma City. Then, nothing...quiet...no explanation! Does anyone know what is going on with these guys? What's my next move? Any suggestions would be appreciated.

Thanks all.