Shipment delivered July 1, only 16/2601 units received, then reverted to “In transit” on July 22. No updates, no resolution.

Shipment FBA18YD27HSF was delivered to Amazon on July 1st. Amazon received 16 units out of 2,601, and since then there has been no progress. I contacted support, and as usual, the response was: “Wait until the shipment closes on September 12th; we cannot provide any information.” On July 22nd, the status suddenly changed to “In transit to pickup location,” with no further progress since. It doesn’t make sense that the shipment was marked as received on July 1st and then changed to “In transit” on July 22nd. What was happening between July 1st and July 22nd? When will the remaining units from this shipment be received and made available for sale? This situation is extremely frustrating. Doing business with Amazon in these conditions is becoming impossible, and Seller Support has been completely unhelpful.