If a financial institution or thrid party platform like Remitly fails to acknowledge your routing number, it is most likely due to their validation system not utilizing the most recent edition of the Federal Reserve's bank routing directory. The instituion will need to update their records in such cases.
The best way to get this routing number updated is by contacting the institution directly as their customer.
You cn use the following template to send over to this financial institutions:
Hi [Institution],
I’m attempting to link my bank account through your service, but I’m getting an error message of [insert error message].
It seems like your routing number validation system does not recognize the routing number [insert routing number here]. This routing number is valid according to the Federal Reserve's e-payments routing number directory.
Could you please help me escalate this to your banking operations team and get this routing number updated?
Thank you,
[your name here]