Claim page: number of tokens mintable by an address in csv

As per Manifold Docs, for a free mint claim page, set up a csv in a first column starting by a cell with “address” on it, and a second column with a cell “value” on top and “1” for each. Alas, Manifold refuses the csv, saying “xxxaddress 1” is not a valid address, as if it cannot recognize the value column as such.