Infomaker-adding attribute to existing custom report

Hello,

I know this should be easy, but it's been too long since I've worked in Infomaker and the documentation leaves much to be desired.  I have a custom report which already has attributes in it.  I've added my new attribute to the stored procedure this report is using.  But I'm getting stuck on adding the new attribute as a field on the report.

I tried copying our kidcode attribute field in order to add this "covid-19 vaccine" field but I'm running into a validation error.  I'm hoping some kind soul can point out what simple trick I'm missing/forgetting.  Thanks!