Unable to connect

Since few weeks, I'm unable to connect my Quatix 5 to my Lumia 950. Pairing the two devices works fine, but the watch is deconnected after 2-3 seconds.
Are there other Windows Phone users having the same issue ?
My phone runs Windows Phone 10 OS (ver. 10.0.15254.547)
The watch is under v 12.0.0.0