Pressalit 2000 Toilet Seat

Hi, can anyone tell me how to remove these toilet seat hinges, they bolts won't turn and just turn the entire hinge in its hole if that makes sense, they need to come off so I can pack out the holes to stop the seat shifting so much, the seat is about 25 years old and a plumber who was here on an unrelated job would not touch it.

I am thinking at this point they may have to be cut off and if so is there anything similar on the market still.

Any help is appreciated

The nut will be seized on. Try giving it a good spray with CRC or similar, leave it for 30 minutes then spray it again.
You will need to hold the top hinge part so it doesn't turn and then get a spanner on the nut underneath and undo it. Once it starts moving you will be ok.
Any new toilet seat will for the holes even if you do have to cut it off.

Thanks Chippy, will do that, do you happen to know what this tool is called? it comes with that particular hinge set to get the nut on and off.

https://i.imgur.com/NtlvjdP.jpg

It's just an open ended socket spanner that fits the nut and let's the thread pass through it so it can reach right up.
A deep socket wrench would work. The tool shown is obviously just a cheap little tool the supply.