I can't connect my Android to any VPN except Kaspersky - How to fix?

I previously used 1.1.1.1 Warp VPN and it always used to work but it made my internet speed slow and so I'd keep it off. Later on, I tried Kaspersky VPN and it worked. I've tried many VPNs in the past too , they never showed any problems, but recently I can only connect to the VPN provided by Kaspersky and when I tried using 1.1.1.1 Warp it doesn't work (because I got premium there and want to use that instead). And that's the same case for all other VPNs I've ever tried, I had them downloaded again and tried to connect, but they all say connection failed and doesn't work. Kaspersky, on the other hand, does work even now, so I think that app changed some setting on my phone as it required but it's preventing other VPNs from working. What should I do? I tried every solution video from YouTube, it still doesn't get fixed.