Wrike Webhooks - troubleshooting connectivity

Hi all,

I am new to Wrike Webhooks.  We have just finished configuring our endpoint server to accept traffic from www.wrike.com on ports 80 and 443.  I successfully created an account webhook and made a change on a project to see if it would trigger the webhook.  I received an email a few minutes later indicating that Wrike could not reach my endpoint.  Any suggestions on how to troubleshoot the connection between my endpoint and Wrike?  How do I ensure that everything has been configured properly on my endpoint server?

Thanks,

Wayne Cox