grammar - Via and its usage

We had a discussion over over the correct usage and meaning of the following sentences.

Sign up via (web.link) or calling (phone number) by DD MMM ‘YY.

vs.

Sign up via (web.link) or call (phone number) by DD MMM ‘YY.

Which would be the correct usage if the intention is the ability to sign up via both methods? Are either or both correct? Is there a difference in meaning?

Cheers to everyone for any help!