I've been having the same problem since "sometime" in mid July...
Maybe this will help:
If I type a message in Phone Link, the message goes to my phone, and as soon as it is sent, it is deleted from Phone Link.
If I send a message using my phone, Phone Link has no record of it.
If someone sends me a message, it doesn't show up in messages in Phone Link.
My eyes are old, I hate typing on my phone, so I have been using Phone Link for at least 3 years:
My PC is running Windows 10
First Phone - Samsung S21 - Never had a problem
Current Phone - Samsung S22 - Never had a problem until the recent Phone Link update
I am running Phone Link version 1.24062.101.0
In the recent update, I was forced to link my MS Partner account to my phone. I never had a problem before that...
As a former Microsoft Certified Partner, and a Software Engineer, I feel confident in saying, this bug was introduced when we were required to register our phones with Microsoft to use the App. Maybe it has to do with that.
I should add:
In PC menu
right click "Phone Link"
click "More"
Click "App Settings"
Under "Reset," Click "Reset" button
Does work, but it will stop working after a few days.
Also, while on the same network, my phone is connected via Wi-Fi, my computer is hard wired. Wi-Fi on the computer is turned off.
I'd gladly move to Samsung DeX, but it's difficult to copy and past text messages, if Phone Link would work, it's easier to use.