From looking at HTML source, it looks like the chat function is hosted on a third party site (z1.liveper.sn). Depending on browser or settings or if using VPN, there might be issues with getting to this site from DL website which causes the endless spinning. They are using the Senegalese top-level domain, and some corporate VPNs can be setup to block content it thinks is coming from certain countries/continents (the content isn't really coming from Senegal as domain belongs to US-based Liveperson, Inc.). It generally takes a couple seconds to connect for me before the "Message Us" button shows up.