Dual Sim Management

Hi I have the Dual Sim Version of the p9. Everything is working well with both Sims except I can not disable the second Sim. But this is essential for me since I want to disable my work Sim when I leave the office. Huawei Website says one has to use the Dual sim Manager...which my phone has not Installed. Tried it with an app from the play Store but found out p9 is not yet supported by the App.

Any ideas?
Thanks in advance

from xda-developers http://ift.tt/2bf8oYN
via IFTTT