I use Nextcloud with Hetzner on a linux machine with ubuntu (but I get the same with my windows laptop). When I want to login to my storage share on either browser (chrome or firefox) I get:
Please use the command line updater because updating via browser is disabled in your config.php.
For help, see the [documentation]
Hello @Jennifer_Girrbach-No,
welcome to the community of Nextcloud 
You started a topic in support category. Unfortunately you ignored the template and a lot of information to help you is missing. Please edit your original post and add all required details like Nextcloud version, webserver type and version, os version, related log file content. Use the support template.
Without additional information the community members cannot help you.
Regards,
wwe
IMO Hetzner “Storage share” is a managed offering and the provider is expected to perform the upgrades. I would recommend you reach outto their support.
If you can get access to any occ interface, you might try an:
occ upgrade
This error is very famous here. For steps beyond that, @wwe has already said it all.
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