Your support form requires a login. But if the thing I need help with is logging in there is no alternative method for me to get support. There must be some way you can offer support on login issues while still protecting yourselves from spam.
a) You could issue everyone a special secret account-specific URL they can use to request support for their account.
b) You could allow use of the support form with login and password only skipping MFA and Authorized IP checks for the support form only.
c) You could allow known email addresses to initiate new tickets via email to firstname.lastname@example.org.
d) You could publish a phone number. Perhaps email it only to your users if you don’t want to post it on your website. Include that phone number in the autoreply when a known email address emails email@example.com?
e) You could force solution of a captcha and verification of an email address for people requesting support without logging in?
Lots of options. Choose one!