Travis CI isn't receiving requests from github webhook,no pull requests

We have private repositories. Travis ci was working fine until recently new pull requests are not shown in travis After merging into master we trigger travis ci webhook it is still sending events request fro github travis ci webhook but it is not reflected in travis ci user interface.
Even I can’t see travis ci details on pull requests like before. In github the last pull request number is 54 but in travis ci it’s 51and not fetching further pull requests, I can’t attach more than one screenshot as I am a new user I can show it is sending notification for latest PR number 54 to travis ci