Service (spanner icon) in forscan -> PATS programming.
https://forscan.org/forum/viewtopic.php?f=5&t=836
The software will walk you through the steps
You do need two different transponder keys to perform a PATS reset/paramter reset. You can use the uncut blank as a second key, but it is fiddly. When the software asks for the second key, wrap tin foil around the first key's head and hold the second key head up next to the first key. This blocks the first key's transponder signal so the car will see the second key.