Openvidu IOS ionic app issue

I integrated openvidu video call in my ionic 4 project.Its working fine initially.But now if I tried to connect the video call I get the error message like
" Error Occurred! There was an error connecting to the session : null is not an object (evaluating 'this.localUser.getStreamManager().on ')".
It occurs only in ios app.In android its working fine.Please kindly support me regarding this issue.

For Ios there are some addtional steps:
see here: openvidu-ionic - OpenVidu Docs

But as I’ve written here I have issues: Issues with iOS and openvidu-ionic-capacitor