When I initially setup my connection I don’t recall having any issue using Yodlee but recently I closed one checking account and opened another with NFCU. But now I could not modify the connection. Tried Plaid, same results. I was getting a “403” message which means I was being blocked at the server (bank’s website) level. So long story short, one option is the call NFCU and ask them to allow access but what I did that worked is open tiller in a “incognito” mode.
Welcome to the forum Abdul! This is definitely something you should work with support about (support@tiller.com). If it’s something on the Tiller side they can help narrow down the issue, or if it’s something with one of the aggregators they can work with them on it.