They probably set your height adjustment to correspond to actual blade height (3" on indicator = 3" cut height). When I done my Turf Tiger I had the same problem. My issue was caused because I was running too low rear tire pressure causing me to have to adjust the deck height too much to compensate. Check your adjusting rod near the deck height pins (one that connects to foot pedal). It will need to be adjusted so you can lock the deck in transport position. If it is like a TT deck, the rear of the deck is hitting the deck stop keeping it from locking in the up position. Easy to fix yourself.