Frame Mint on Base - Missing contract data: undefined

hi,
I’m trying to create a mint collection and in the last step trying to publish, I encounter this error message:
Missing contract data: undefined
What’s wrong? I tried creating different contracts, but I can’t find a solution,
can anyone help?
Thanks in advance

gm! Which contacts did you try creating? You’ll need an existing Base ERC1155 contract. Do you have one published?