Webhook Url is Invalid

Hii Team,

          Currently we are trying to use webhook for getting back the signed document. But in the creation of webhook itself, we are getting an error that "webhook URL is invalid". We have tried becceptor for testing purpose. So it worked there . But when we tried with our production environment's webapi URL, we weren't able to create webhook. 

          We were thinking that due to change in the webhook url which contains special characters like "@" , ":" and few like that in text, for autheticating our webapi URL.

          Does adobe is making validation over the webapi URL? If someone is facing similar kind of issues, assistance over this will be really helpful.

  Thanks in advance.