I have V2 webhook created for a custom application on Box Developer Console. Whenever any file upload takes place from file request URL the webhook that is setup is not triggering instantly , earlier this functionality was working totally fine. Its triggering at delay of 10-15 minutes. I checked the endpoint in webhook and its correct also the action on webhook is selected i.e FILE UPLOAD . 

We have emailed to the support team from our organisation . You might have received an email from Subhasish. Requesting for an immediate support as it's hindering our project release.