I too have faced same issue today in afternoon when i tried applying for this. Kuch aage hua bhai resolve ye issue ? If anyone else has faced the same kindly share the remedy.
its very tricky you need to talk customer care on this matter else you can check self, try to apply new card through axis app if pre-approved cards list showing then You can apply for pro card if getting error then you need to close one card before applying pro..
So @spatone I have 3 Axis + 1 Citi card migrated to Axis- You mean to say I won't be able to apply for Pro Supercard even if I close 1 axis card out of the 3 I have?