Usually I would ask you to provide the currently used software version as this would be the minimum requirement for any new post.
The SSIP7000 is neither Skype for Business certified and was never LYNC certified or compatible so your case is not a supported scenarion and should not even work.
Officially supported phones are listed => here <= and the SSIP7000 is not one of them.
As we already supplied enough information within this post to solve or diagnose the original posters issue and they never got back I will close this to prevent any other off topic posts.
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