Attaching implements on my 2018 New Holland T4.75 Tractor

[bmackinlay]

Having difficulty getting the arms to lock down on my front end loader They engage but will not lock down Recently I was picking up round bales and spear would sometimes stay in bale when I would back away to get more hay. I have even used a cheater bar and still will not lock in ! Any advice would be appreciated! Dealer wants $300.00 to come to farm and take it to their shop to look at it . It only has 45 hours on it mostly idling time!