I am told my work email is "not a valid" email

I have been granted access to a fair amount of videos under my work email, but only can login with my personal email. When I attempt to create a new account with my work email I am told repeatedly that “it is not a valid email”  even though no authentication has been run yet on the email, and yep I am sure I got it all correct. Because of the various numbers of people sending me information it really doesn't seem professional to tell them “Oh Box can't figure out how to register this email, please use my personal email”