No help for the small businesses

I started using MailChimp to do campaigns to promote my small business, for the first month or two it was fine but now they don't seem to recognise a Gmail account which means majority of my subscribers don't even get my articles. I put a lot of time and effort into creating campaigns and articles, trying to get new subscribers when majority of my audience doesn't even receive them. Waste of time and effort, they have no regard for the smaller businesses and will probably only assist if you pay for the service. They never get back to you when you report it either. Rather don't offer the free service then.