The picture wouldn’t load for me and for some reason I interpreted your issue as some really stubborn truck nuts someone stuck on as a prank 😂

Are they the kind that have two parts with the middle part popping up? This kind uses the middle part to lock the outside in place and you have to pull the inside up first before you take them out. I’d also recommend buying a tool to remove them like this https://www.amazon.com/XBRN-Removal-Window-Fastener-Remover/dp/B08GKK5ZTL

If they spin, I almost wonder if they operate more like zip ties than nuts. Maybe see if you can use a hook of some sort to release the bite on that ribbed portion of the side. Ultimately, if it’s not really meant to be replaced DIY, the shop may view plastic fasteners as a disposable item that will be replaced as a consumable.

Also, more optimistically, what part of the car is this? Often, you can find the “official” name of an assembly on a dealer’s parts website, then look up how to replace it on Youtube. Sometimes, snuck into the middle, the mechanic will show how to deal with whatever weird little automotive fastener is part of the assembly they’re replacing.

For some reason I can’t click on your image link. Can you post it in the comments?

Can’t give advice for getting them out. But please, for the love of God, before you even attempt to take them out. Get spares. If you’re not sure which ones exactly. Try to get ones that are mixed but look similar.

If you do t use extreme precision and care. You will more than likely break it. It happened on my car. Granted, mines more of a cheap city xar to get from one place to another, bit still.

Some of these need to just be turned a quarter turn and then lifted out, but I can’t say for these particular ones. I assume you’ve tried pulling them out with at different positions.