Problems with GTIN Acceptance - GTIN vs EAN?

Hi!

I’m trying to list some new products and have come up against an issue with getting Amazon to accept the GTIN.

We manufacture our own products. We have an account with GS1, and assign what were EANs from there. GS1’s home page seems to suggest that EAN (European Article Number) and GTIN ( Global Trade Item Number) are synonymous.

I’ve put the new product descriptions into the GS1 account and saved them. They’ve been on the GS1 database for a fortnight now, so it’s not a propagation delay. However, the Amazon listing tool is not accepting the numbers, regardless of whether I select GTIN or EAN.

Is anyone else having a similar issue, and does anyone know how to resolve this, please?