new emails staying on xfinity server only after email migration to yahoo

i was finally able to complete the migration steps to migrate comcast.net email to yahoo and received email that migration was completed/successful

however, new emails are still on xfinity server and no new emails are on yahoo

i am using web browser to look at emails for both xfinity and yahoo.

i have migrated 2 other comcast.net email accounts with no issues

and I've tried multiple browsers on multiple devices to make it not a cache/cookie problem

how can resolve?