Issue with WebGL game on itch.io - Error after a certain time passed in main menu

https://ibb.co/j451gZg (error message)


I recently created a WebGL game using unity (I'm new in unity and this is just my 2nd game) and uploaded it to itch.io to test it. However, When the game is launched and left idle on the main menu for around 5-10 seconds, an error message pops up.

RUNTIME ERROR: NULL FUNCTION OR FUNCTION SIGNATURE MISMATCH
https://ibb.co/j451gZg

But, if I press play button (change scene) before the said time, the game runs perfectly fine.

I tried to play the game in the unity editor and it also runs perfectly fine

I'm not sure what could be causing this issue, and I'm hoping someone here might have some insight.

Thanks in advance for any help you can provide!

TLDR: when i play the game and let it stay in the main menu for 5-10 secs there will be null function or function signature mismatch but when i click the play button before it gives me the error I can play the game perfectly fine

 

Which unity version?
URP?