I personally do not see how this is even getting the correct image ID
$image = $bank->bank_logo;
ACF does not get the post attachments and add them to the post array when getting the value of a relationship field. If this is being populated it is not being done by ACF. If it does contain the correct attachment ID then you need to look into how that value is being populated. That is where you’ll find the cause of it being an ID rather than a url.
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