Hi Thamara,
Thanks a lot for your good response. But, I don't know why it is getting connected for sometime if it is not lync certified. Also, I have been in contact with Yeastar company to fix this issue and they know we are using this with skype for business 2015
but they did not tell as any limitation on these gateways for SFB?
Also, is it possible if we disable OPTION request somehow being send to the gateways so it work properly?
Please guide.
Many Thanks