Nextcloud Version Not Maintained

I am getting this message in my Nextcloud admin panel.

The version you are running is not maintained anymore. Please make sure to update to a supported version as soon as possible.

It says I am using Nextcloud Hub 4 (26.0.13)

My android app is complaining about this, which is why I started looking at it.

Updating MIAB only takes me to Nextcloud version 26.0.13

Is this a known issue, or am I doing something wrong?

miab uses only a subset of a complete Nextcloud server für calender, contacs and files (never used it). With NC it very hard to keep on track because of their fast changing versions. A NC App complains it, because it is not made for miab.

just my 2 cents, hope it helps…

Maurice