Unknown reason for unable to vassal an independent city

[deathruin]

My current Vassal Logistics reads this:
Current effect: 267 Imperial Miles

But when I view an INDEPENDENT CITY(not vassal) 252 miles away, the vassal button is greyed out:
I do not need another centralization level, I, in fact, can vassal independent cities that are closer to me and also know I have the spot as I recently dropped a vassal.
I should not need higher level logistics as per number posted above
It is an independent city so the "exclusive zone" rule does not apply.

So, what could possibly be wrong?

deathruin of realm 160.

PS. I think all the logistics have been recently adjusted because I'm fairly sure they were all of lower value... Maybe that's causing the issue?

[Muwe]

The team is currently working on fixing this issue. It will be resolved at the shortest. Thank you