if it's grinding with the clutch pushed all the way down, and won't engage without grinding, the secondary clutch isn't releasing all the way. Could be a lot of reasons for that. Linkage. Throwout. Smoked clutch. Etc.
12 hours doesn't seem like much but I've seen them destroyed in under 1 hour use, so improper use can hurt it pretty quickly. This is almost exclusively with gear drive tractors that have a loader, never have to put a clutch in an HST tractor. Well one or two, but not dozens like the gear drives.
Might try to adjust it first.
One can pull the inspection plate (if accessible) and sniff inside the hold. Does it smell like burnt brakes? If so...get ready to buy a new clutch. Per the warranty booklet, Warranty doesn't' cover clutch and brake linings, they're considered wear items. BUT if there's something defective that caused the clutch to slip and burn, they might help with that. But the dealer will have to prove that defect.
Worth mentioning, but those have a 2 stage clutch. You push the pedal down, about halfway it should kinda get a little stiffer. That's where the second stage starts to disengage, which is for your PTO. To disengage the PTO clutch enough to pull the lever up without grinding, you have to push the pedal ALL the way down, which is why linkage adjustment is critical. The WSM outlines it.