Unable to install a custom app

Hello Team,
We have created a custom app (Cron App) in the instance (https://newaccount1625467973288sandbox.freshdesk.com/) but unable to install the app. Can you please help us out on the issue?
Thanks,
Jagadish

HI @Jagadish,
Welcome to the community!
Can you please explain more detail about the issue, that might help us to understand the problem even better
is there any error which you are getting in the console
kindly give us the App ID to investigate further

Thanks

We have developed a custom app by name Cron APP, while installing it in the instance, it is throwing error, that there was an error during installation, please contact support team. Please look into that app and suggest us a solution, thanks

https://www.freshdev.io/custom_apps/42837-cron_app/edit, please check that url

Do you see any error in the browser console, network tab or in the UI, @Jagadish ?