looks like you need to get to level 60 before you can rank up.
I have 2 other champs at rank 4… is this new?
even though you have the T7Basic needed, they actually have to be held in Inventory (not overflow Stash) in order to be used for Rankup needs.
so probably assume you had previously ranked up others while you were on the Sigil Subscription (or Sigil Trial period), when Inventory limits are increased.
or (doubt it), maybe you had just done another, and did not go to Stash to claim some Stash to move over to Inventory (most of the time that is automatic, but sometimes you need to Claim manually from Stash into Inventory).
** and as to what was previously mentioned (needing to be Level 60), if you are OFF of the Sigil, agree, that is probably what is needed to continue to rankup more champs to that rank.
I appreciate the comments. I'm still on Sigil, rank up says max 2/2 + 1 in stash we all know you need 3 for rank up to R4. Just thought it was a bug, as normally you can pull from stash for rank up. Having 2 other champs at R4, I felt this was really strange. Submitted a support ticket and received nothing but a closed ticket for a response.
Then did you maybe get to r4 on those other champs by using a Rank-up GEM ?? (that would bypass using the Cats that you would be short of otherwise).
And so maybe, before reaching Level 60 (not gonna dig up my Cat Murdock Rank-up Gems Requirements chart right now), the Sigil is maybe giving you a bump-up in Inventory, but being below Level 60 that Sigil bump-up is still not quite enough for the T7Basic's that you need.
And, NO, you can NOT get to count any overflow Stash towards being usable for a Rankup. Your Inventory itself (without Stash) has to be able to hold enough of them in order to meet the requirement.