Can't playtest on roblox studio with a VPN

Hi. I have recently had an issue when I use the playtest on roblox studio with NordVPN on, it will just not load my character, and a few seconds later give me “Failed to connect (a string of numbers); no response”. But when I turn off my vpn I do not get this error. I have tried changing the vpn dns, changing location, reinstalling studio and restarting my computer. All suggestions appreciated. I am using Windows 10.