unpaid royalties in Jasper County Texas

Thanks to the advice of Ms Barnes, I used the RRC website to look to see if there might be some wells on some of the inherited properties my wife has in Texas. Most of what I’ve been able to find seem to be dry wells. But there was a lease she signed back in 2010 right after her inheritance was probated. A well was drilled on this lease in Jasper County called Roganville Turner A-39, lease ID 262415. This well paid her one big royalty check the first year, around $1700 in 2011 and then immediately dropped to $5 or less for the next four years and then just stopped paying altogether. We just assumed the well wasn’t producing anymore. It seems very strange to me that a well would pay $1700 the first year and $5 the next but what do I know. Last week I discovered Anadarko then sold the well in 2015 or 2016 to Zarvona Energy, LLC. That is around the time the checks completely stopped. So from what I’m seeing on the RRC website the well is still producing and has been for years. I’ve been emailing Zarvona who uses PAK Energy, a third party company, that handles Owner Relations for numerous companies. So far just cryptic messages are going back and forth.

So to make a short story long,

How far back in Texas can we go to recover unpaid royalties?

Is interest owed on this money?

Also, am I reading the RRC website correctly? Is this well still producing? Could it have been offline for years?

Thank you for any help. And thanks to Ms Barnes for pointing me in the right direction.