Does it mean : no matter which app I choose to install from “Apps” ?
Does it mean : the installation is successful despite of the error message ?
(In case the installation is unsuccessful, you could use Aurora Store instead.)
You could try to clear data of “Apps” in order to reset it:
Settings > Applications > Apps > Storage > CLEAR DATA > OK.
If the issue still occurs, the best practice is to open a “New issue” on our gitlab, with some logs attached. Make the bug occur before triggering the creation of the log file please.
A second method to catch logs is available here but only if the first one is too complicated for you.
If you need anything, just ask.