Re: parker problem !
Are you referring to the string latch not resetting after being shot preventing the bow from being fully cocked? This is a relatively common occurance with Parkers. Easy fix is to hold the ADF device down with a screwdriver then pulling the trigger. Should reset everything. Make sure your safety is in the fire position when cocking the bow as well.
Should be a isolated incidence. If that is the problem and it continues, the trigger box may need replaced.
Also, if you suspect excessive serving wear, run a cotton swab around the string latch. If there are any burrs, they will be easy to see. Take very fine abrasive and smooth out the burr.
Just guessing here based on the info in your post.
I support all hunters, regardless of weapon or technique!