Tire Inventory Account w Large Discrepancy

We recently completed our full physical inventory on 10/31/21 and I have a dilemma on my hands that I just can't figure out so I am hoping someone can explain reconciling the tire account process that is supposed to take place in the accounting regularly? We try and keep roughly 80 tires in stock at an parts inventory value of between 12,000 and 14,000 at any given time. When we did our full physical inventory we counted 16,027 worth of tires with a unit count of 98 tires on hand. Everything looks correct and I am feeling good about the inventory until accounting tells me that they show roughly 70,000 worth of tires in stock!! I say there is no way that we would ever have that many tires in stock at that high of a value amount so your accounting is wrong and I can foresee the blame game starting.
I have checked the following on my end: we have all of our tires in a stocking group 109 which places them into the tire inventory account 243 when we purchase and post in the tires, we verify that we are inputting the correct cost of the tire vs what we are billed by GM so that checks out correctly with the cost of the tire being correct when put into inventory and when sold on the RO, my sale account number is 490 and the cost of sale account is 690 and when I looked back over the past 11 months of transactions all the details look correct. The 490 and 690 accounts are hitting the 243 account so I would believe that as we buy and sell tires the 243 inventory account would balance out like our 242 parts account does which our parts account was right on the money. I called DealerTrack and they looked into the situation and they are telling me that nobody in accounting is reconciling tires and that is the reason for the large discrepancy. They tell me that the tire account has to be reconciled manually to make it balance out and I am not fully understanding that process of what needs to happen? I just want to make sure that all my bases are covered before I march into accounting and say that the tires problem is on your end because you are not reconciling the tire account. If anyone could explain how the tire account 243 is handled differently that the 242 account, I would appreciate it.
I have checked the following on my end: we have all of our tires in a stocking group 109 which places them into the tire inventory account 243 when we purchase and post in the tires, we verify that we are inputting the correct cost of the tire vs what we are billed by GM so that checks out correctly with the cost of the tire being correct when put into inventory and when sold on the RO, my sale account number is 490 and the cost of sale account is 690 and when I looked back over the past 11 months of transactions all the details look correct. The 490 and 690 accounts are hitting the 243 account so I would believe that as we buy and sell tires the 243 inventory account would balance out like our 242 parts account does which our parts account was right on the money. I called DealerTrack and they looked into the situation and they are telling me that nobody in accounting is reconciling tires and that is the reason for the large discrepancy. They tell me that the tire account has to be reconciled manually to make it balance out and I am not fully understanding that process of what needs to happen? I just want to make sure that all my bases are covered before I march into accounting and say that the tires problem is on your end because you are not reconciling the tire account. If anyone could explain how the tire account 243 is handled differently that the 242 account, I would appreciate it.