I am still experimenting. Mine doesn't stop anymore but i don't know if it will mine anything. I have left it up for hours without result. One thing that can help with yours is putting your own node URL in the ETH end-point on Koinos. You will need to do a quick sign-up here: https://infura.io/

Then create a project, name it and it will generate a url that you can copy and paste on Koinos at the top right where it requires an ETH endpoint.

You can find more general info here: @nickyhavey/havey-s-guide-to-mining-koinos