GitLab.com new paid subscription purchase flow throwing error

Summary

User has reported receiving Failed to confirm your order! Please try again. when attempting to by a paid subscription within GitLab.com.

Possible Root Cause

The new registration with checkout flow creates a group name from the company name automatically, but doesn't validate or sanitize the Group Name input. The save fails and we get a cryptic error message

Workaround

Avoid commas and other disallowed characters in the company name

Solution Suggestion

Sanitize the Group Name input, in such a way that it conforms to the rules set in the original group creation screen, as partially seen in the screenshot.