Undo the effects of changing meta_key from Varchar to int

I was trying to edit the email form field so that it accepts int values like of a phone number. I knew very less about how database values work and this is what i did: 1. Figured out that email field was "hrb_email" 2. Found that in wp_metauser hrb_email is a meta_key 3. Went to structure> and changed the meta_key from varchar to int.

Result: I cant find hrb_email in wp_metauser any more. Wordpress dashboard shows no users. Although wp_users has my user details. Also, on my website, I can see user if I manually put the URL for those users but I cant find them on the list on my website.

Please advice. Note: changing the meta_key value back to varchar does not help.

This is what meta_key looks like

Updated the meta_key fields manually for each user. To achieve this, I created a couple of new users and understood what values belonged to the key fields. From that, i started updating the meta_key field manually. It worked for all the users, except that i had to update password on Wordpress>dashboard>users>edit.