Can't remove the barrels from the action.

[B. Dudley]

Yes, try uncocking the gun, then removing the forend and see if they will come free.
Some Parkers are just like that and they need to be dry fired before taking down.

If not... then it could be any number of things. usually just very dirty and needing cleaning or an issue with the unhooking slide. Could be a stuck slide or a broken slide spring. This is not an uncommon problem and I have repaired a good amount with either one of the aforementioned issues being the root cause.