Can't access or create S3 Buckets

Background: I have this AWS account from back when EC2 was launched as a beta service (2008?) and have S3 buckets created for over a decade. I haven't very actively used the console or the AWS account in the past 5 years or so. Maybe my last login was back in 2020 or 2021.

When I recently logged into AWS console, I was shown a message that apparently my account is now considered a "root" account and I'll need another user account to access my S3 buckets/files. Since then I've tried the following, but still can't access my S3 buckets.

1. I created a new "Identity Center" account, which for whatever reason I can't login to.
2. I had a couple of existing "IAM" accounts which I've used for various services including S3. I turned on "Console Access" on one of them and was able to successfully login to it.
3. Using my root account, I've also created a policy to include three policies related to "StorageLens" and attached them to the IAM user.

I still keep getting the error "You or your AWS administrator must update your IAM permissions to allow s3:GetStorageLensConfiguration and s3:GetStorageLensDashboard. After you obtain the necessary permissions, choose Refresh. Learn more about Identity and access management in Amazon S3"

Any ideas what am I missing or how can I identify what's going on with the permissions?

Thanks!