Poly VVX and 3PIP

 Poly VVX 201,301 and 401 running 3PIP

After migrate one of my customer from Skype for Business server 2015 and hybrid, with Enterprise voice we started to plan for the VVX together with 3PIP.
For some time we saw that the VVX phones where working fine, but some started to logout for some reason after 48-72 hours. And the we was not able to login to them again.