Do I need an EORI number ?

[C2019]

I am a sole trader and I sell fine art globally that I have created myself. I purchase materials and what I need from various places in the UK but I got told today that I’d need a EORI number from a fellow artist if I wanted to sell my art to countries outside of the UK. I’ve been sending my work all over the world and I’ve only ever had to fill in a CN22 form to stick to the parcel and normally everything gets there with only a slight delay on some items. I don’t even fill in the commodity codes for the parcel ( under the advice of the post office ) and they still get there.There is not even a space to put a EORI number on a CN22 form and Royal Mail or anyone at the post office never mentions it, a lady at the post office had never even heard of it like I hadn’t when I spoke to her earlier. Will I need one to send my artwork like I am doing or is it not required? I’ve sent one item to Europe and it’s got there but the lady receiving the parcel says she has to pay a customs charge but I’ve not had anyone get in touch asking for such a number. I’m a little lost on all this

[gt94sss2]

https://www.gov.uk/eori

[C2019]

I’ve looked at that about 10 times prior and it answers nothing. I asked today again at the post office and they said they had never heard of it and to just keep using a CN22 and that such a number wouldn’t change anything