Their Api Does Not Work and Tech Support Is Unwilling to Help, Plus They Ignore My Request for a Refund

I signed up for MailerLite with the intention of using their API to add subscribers based on the actions they take on my website. For example, some users sign up for a newsletter, and others purchase a paid subscription. However, their API did not work for me. I followed their instructions exactly but got an error that prevented me from adding users. This means that the tool was completely useless for me, it simply did not work at all. I wasted many hours on setting it up initially and then unsuccessfully trying to fix this error. Unfortunately, their tech support was not helpful. And after 4 days of not receiving an answer, I canceled my account and requested a full refund. Now they aren't even responding to my request for a refund. I have done business with many companies online, I think this customer service is among the worst I have ever experienced. I have reverted back to my previous email service provider and I seriously recommend avoiding doing business with MailerLite, they are absolutely terrible and don't deserve your business.