Listing not updating also tried Via Upload, asin taken by someone else?

hello everyone, i have been trying to get the support for 1 week but the support cant seems to help me, i made a listing 2 months ago, im brand registered and bought the GS1 asin, for some reason i cant update my listing, when i click edit the changes that i make it will say saved but it wont save even if i wit 24 hours or 48 hours the changes wont apply, the brand support and non brand support are saying ,

After looking into it, I found that the attribute you would like to update for this ASIN has already been claimed by another representative of the brand.

While we are unable to make updates per your request, we recommend that you reach out to the account of the winning contributor in order to agree on the changes. Once you both conclude on the new values, the owner can make the necessary updates via Seller Central.

i do not have any brand representative and im the only one selling on my listing, i told them many times but they all send me here https://sellercentral-europe.amazon.com/abuse-submission/index.html
i cannot report my self it wont let me do it. can please somebody help me ?