The value specified is invalid: SIZE SYSTEM ERROR

Hi there! Hope you can help me with this issue today.

I uploaded all my products to the Spanish marketplace and now want to add them to other countries within Europe to set up PAN-EU FBA. Now, I get lots of errors when trying to add the ASIN’s of my existing products to other marketplaces. I mainly sell clothing items and this is the error I keep getting under Vital Info -> Size Map etc.

Screenshot 2021-06-06 at 12.43.48.png 2144×1452 213 KB

What can I do to resolve this? For example, here I am trying to add a One-Size bikini to the Dutch market. All the errors keep coming and it doesn’t matter what values I enter. When trying to add the same bikini to the UK market, it gives me the exact same errors… over and over again.

Please assist! Thanks a lot!!

Ps. I have refreshed the page like 10 times already during 5 hours and I am trying multiple days to upload it.