Out-of-stock items from my supplier's stock must also be automatically out of my stock through the API system.

My shop works through the API system that connects it to that of my items supplier. The problem is that for a few weeks, the "sold out" items are no longer updated. That is to say that the "sold out" items of my supplier must also be automatically signified as not available in my stock but this is not the case. These sold out items always show up as available in my stock.