I see Coppinpr has beaten me to it, but I'll still post mine anyway.
Before we go the lengthy written description of what to check and how it works in order to see whether the problem actually is the reel strips or reel bundle itself.
It might only be dried grease defeating weak springs, or an escaped coin fouling something, or a missing spring blah, blah.
Force one of the lower payouts that are not performing and take a photo of the vertical fingers that clunk across into the payout disks. That's from the right hand side looking at the mech from the front. They're near the top.
If the payout symbols on the front are right but the fingers can't access holes in the payout disks, then yes you have got them out of sequence.
If that is your issue you need to search the payout discs for the jackpot payout, which allows the correct finger to penetrate all three disks. Then look at the front and if the symbols are wrong, that's when you start moving reel strips to match. If you have more than one jackpot combination then you need check Melons as well as Bars.
If it's not, then the photos will help.