Mondo calls are Spam

This company calls me early in the morning at 7am everyday or during my office hours repeatably with different numbers if you don't answer, and I told one of their consultants earlier that I am good I don't need a phone. Either they sell user information or they purposefully spam people I don't know with what intentions at 7am in the morning.

I went to https://www.mondo.co.za/support/opt-out to opt out but the form on the website does not even submit the opt-out form which is usually a tactic done intentionally cause every other form works but they poorly maintain the Opt-out form?