@faisal have you followed the instructions from here: https://buddy.works/knowledge/standalone/integration-bitbucket ?
The most important part is:
Set up the Webhook address. The webhook is an URL to which Bitbucket will send information on changes in the repositories. The address must be available from the outside: if your installation is assigned to an internal IP (eg. 192.168.x.x), make sure to paste your external IP to that field and redirect the oncoming traffic on your router to the address of your Buddy GO instance.
Most of the problems are caused by the network configured in a wrong way and the connection between Bitbucket and Buddy's machine is not working properly as well as a result.