SUMMARY
I noticed that a couple of my computers (HP Prodesk 400 G6) running KDE Neon (5.26.3), the Update notification says it's offline.  However, on my laptop (Asus UX370uar) running the same version of KDE, has the notification enabled.  I believe this phenomenon happened since 5.26.0

As an experiment, I install KDE Neon using the same ISO (neon-user-20221106-0714.iso) to all my computers and laptop.  And I noticed the same thing right after booting up from the fresh install.  I manually did an update on the computer hoping the issue will be fixed, but to no avail

I have attached the screenshot of the notification from the computer (HP Prodesk 400 G6) and the laptop (Asus UX370uar).


STEPS TO REPRODUCE
1.  Click on the notification popup
2.  Check the Update status

OBSERVED RESULT
The Updates Notification shows "offline" (has a red x with a disconnected plug icon)
 
EXPECTED RESULT
The Updates Notification should have a icon with a up arrow inside a circle

SOFTWARE/OS VERSIONS

Computer (HP Prodesk 400 G6)
=========================
 Operating System: KDE neon 5.26
KDE Plasma Version: 5.26.3
KDE Frameworks Version: 5.99.0
Qt Version: 5.15.7
Kernel Version: 5.15.0-52-generic (64-bit)
Graphics Platform: X11
Processors: 12 × Intel® Core™ i5-10500T CPU @ 2.30GHz
Memory: 15.4 GiB of RAM
Graphics Processor: Mesa Intel® UHD Graphics 630
Manufacturer: HP
Product Name: HP ProDesk 400 G6 Desktop Mini PC


Laptop (Asus UX370uar)
====================
Operating System: KDE neon 5.26
KDE Plasma Version: 5.26.3
KDE Frameworks Version: 5.100.0
Qt Version: 5.15.7
Kernel Version: 5.15.0-52-generic (64-bit)
Graphics Platform: X11
Processors: 8 × Intel® Core™ i7-8550U CPU @ 1.80GHz
Memory: 15.5 GiB of RAM
Graphics Processor: Mesa Intel® UHD Graphics 620
Manufacturer: ASUSTeK COMPUTER INC.
Product Name: UX370UAR
System Version: 1.0