Bot was not able to join the voice channel as - Connection not established within 15 seconds

I think there is some problem with glitch because when my glitch project is not opened in my pc and while using my discord bot to play music, it shows this error ** Connection not established within 15 seconds.** which doesn’t happen when i’m keeping my bot online using vscode. i shifted to glitch yesterday and i am using uptime robot to ping the bot every 5 minutes and it works fine. can anyone tell why this error comes up? my friend also has the same error who is using glitch to host his music bot. Strange thing is this error doesnt come up when my project is opened in my pc, but the voicechannel joining time by the bot is delayed by 3-4 seconds, whereas in vscode there was no delay, bot used to join instantly.