I don’t use VPNs, but plenty of sites using datadome.co will arbitrarily block me at my residential ISP. datadome.co will first ask you to complete a captcha, and upon your success, you are immediately blocked with no recourse. Here’s a typical screenshot: (not mine)

The “contact support” link opens a contact form that goes to a black hole. I’ve filled out dozens, and never gotten a response.