Many of the symptoms and possible fixes are mentioned in this active thread Phone Link App does not open/start
There are still a lot of users without a solution. Since it is now a default OS app, there is no longer a Windows Store app. I tired everything discussed there, but all I get is a few seconds of the splash screen.
The " Turn on Phone link" button brings up nothing more that a two second splash screen, which them disappears, but that's all. The "Manage devices" button does not respond at all,
Here's one thing I have never seen reported. The "Desktop" entries we see, apart from the fact that one says "connected", are identical (same identifying code under the blacked out part). If I simply touch the "connected" one, it immediately changes to disconnected. None of these five items are accessible, and cannot be removed.
This can't be normal. My guess would be that this is clearly related to the problems on the PC. Can someone at least give me a clue as to how I get rid of this mess.