Can someone provide some input?

you probably have an error with the theme or extension, try deploying one by one until you identify which one is causing the error, then review the source until you find the error.

It is a new account and doesn't have any extensions installed yet. Only a base theme is there.

Go to Customizations -> Scripts, look for the scripts with the name starting with: "SC ExtMech" look into their deployments for each one of them and make sure you have a good concurrency and priority standard or higher

@Sohan Kumar Dash review all the Map/Reduce queue script, the most probably reason is that there is another Map/Reduce script running that is taking hours, the activation Map/Reduce throws that error after waiting 1 hour in the queue.