Major issues with Stranded Inventory

I am a moderate volume FBA book seller and have been doing so for several years. Over the past two weeks. my Stranded Inventory has blown up. It seems with every shipment over half the books are going straight to stranded for "inventory error". It's normal to have a handful that either fix themselves or get stuck in stranded forever. But, at this time I have gone from 5 or so to over 150 books stranded and more added daily (over 20 yesterday alone). I am processing my books the same way I have for years. I have an excellent performance index and account health.

The only recourse I can find is to open a ticket on each and every item and I have done so on several and I get one of two responses:

1. "We have refreshed the item and everything is good to go."

2. "This is a simple fix." Simply delete the item, relist using the same sku and ASIN, wait for it to show up in inventory, then change to "fulfill with FBA". This is a 10-15 min process and there is no way I could do this with the amount they are adding daily.

I'm just wondering if anyone else is seeing a spike in their stranded inventory and if anyone has any insight. Also, I cannot seem to find the "call me now" button anymore to actually speak with a human about the issue.

edit--after scouring the forums I should add that I am not using a 3rd party app. I am listing directly with Amazon's "add a product" tool.