My internet keeps disconnecting while gaming. With a VPN, it works fine. Why? (i'm using Virgin Home)

Hey guys,
The connection always drops when I play any online game like Final Fantasy XIV or MHUR. Even my Nintendo Switch disconnects when I play multiplayer games.

I discovered that when I run a VPN program on my computer, the disconnecting issue completely disappears, and the ping level even improves a bit. That’s why I want to know the reason behind this and how I can resolve this issue.

I’ve talked to Virgin call canter multiple times, and the last time they asked for a screenshot. Of course, it’s difficult to capture a screenshot of a problem like this because the disconnection lasts only a second or two. For someone watching YouTube or streaming, it’s not an issue, but for someone playing online, that’s where the struggle is.

We’ve had this issue since swapping from sky to virgin. I saw one post on their community forums talking about dns servers, I manually changed out kit to cloudflare’s (1.1.1.1/1.0.0.1) and it stopped happening, apparently something to do with VM’s filtering(?) I couldn’t access reddit until I swapped dns, and the parental controls are off