IM conversation Window is not getting closed after video call/conversation ended through "Red"-Phone hangup

Hi,

We have issue in closing IM window automatically after video conversation is over. This issue is causing lync to go in a bad state after 7-14 video calls. {Skype for business client}

Issue : We have issue in closing IM window automatically after video conversation is over. This issue is causing lync to go in a bad state after 7-14 video calls.

Observation: In our Team some section of users using Skype for business and some of us using lync 2013 client .Those who are migrated to Skype for business they are experiencing above mentioned issue.

Is there any API/SDK difference between Skype for business and Lync 2013 client ?

How to resolve IM not closing issue with Skepe for business client ?

The following is the version information for Skype for business.

15.0.4719.1000

Thanks