Invalid Add-On Repository / DNS Issue?

Describe the issue you are experiencing

Hello,

I cannot grasp the Background of this Issue and (in my beginner Opinion) Homeassistant doesnt really show me that much information so I am opening an Issue because I cannot really diagnose anything here.

Basically every new repository I want to add I get the Error Message "Invalid Add-on repository!". This happens with some of the Repositories I tried in the last few weeks, for example:

https://github.com/jm-73/Indego https://github.com/fondberg/spotcast https://github.com/Apipa169/Assistant-Relay-for-Hassio

Weirdly enough, the last Link works.

I have tried to restart the System (Host) then adding it, I have disabled my DuckDNS Access, I have tried to change the DNS Server over SSH (CLI) to 8.8.8.8 via "ha dns options --servers dns://8.8.8.8". Nothing changes. I have read some other posts that stated that DNS is falsely setup. My router uses the standard Telekom DNS.

Whats also interesting, although I dont know if that has anything to do with this issue, if I try to "Manually install" the addons by dragging them into the custom_components folder, they are not installed after I restart the host.

What is the used version of the Supervisor?

supervisor-2021.06.8 (beta)

What type of installation are you running?

Home Assistant OS

Which operating system are you running on?

Home Assistant Operating System

What is the version of your installed operating system?

Home Assistant OS 6.1

What version of Home Assistant Core is installed?

core-2021.7.4

Steps to reproduce the issue

Paste the Link in the HACS Repositories section
Try to Add repository
Voila: "Invalid Add-on repository!" ...

Anything in the Supervisor logs that might be useful for us?

21-07-25 15:24:54 INFO (MainThread) [supervisor.store.git] Cloning add-on https://github.com/jm-73/Indego repository
21-07-25 15:24:55 ERROR (MainThread) [supervisor.store] https://github.com/jm-73/Indego is not a valid add-on repository
21-07-25 15:24:55 INFO (MainThread) [supervisor.resolution.module] Create new issue IssueType.CORRUPT_REPOSITORY - ContextType.STORE / b35b8ccd
21-07-25 15:24:55 INFO (MainThread) [supervisor.resolution.module] Create new suggestion SuggestionType.EXECUTE_REMOVE - ContextType.STORE / b35b8ccd
21-07-25 15:24:55 WARNING (MainThread) [supervisor.store.data] No repository information exists at /data/addons/git/b35b8ccd
21-07-25 15:24:56 INFO (MainThread) [supervisor.store] Loading add-ons from store: 63 all - 0 new - 0 remove
21-07-25 15:24:56 INFO (MainThread) [supervisor.resolution.fixups.store_execute_remove] Remove invalid Store: b35b8ccd
21-07-25 15:24:56 INFO (MainThread) [supervisor.store.git] Removing custom add-on repository https://github.com/jm-73/Indego

Different Log Entry:
21-07-25 15:29:30 INFO (MainThread) [supervisor.store.git] Cloning add-on https://github.com/fondberg/spotcast repository
21-07-25 15:29:31 ERROR (MainThread) [supervisor.store] https://github.com/fondberg/spotcast is not a valid add-on repository
21-07-25 15:29:31 INFO (MainThread) [supervisor.resolution.module] Create new issue IssueType.CORRUPT_REPOSITORY - ContextType.STORE / d27bc1c4
21-07-25 15:29:31 INFO (MainThread) [supervisor.resolution.module] Create new suggestion SuggestionType.EXECUTE_REMOVE - ContextType.STORE / d27bc1c4
21-07-25 15:29:32 WARNING (MainThread) [supervisor.store.data] No repository information exists at /data/addons/git/d27bc1c4
21-07-25 15:29:32 INFO (MainThread) [supervisor.store] Loading add-ons from store: 65 all - 0 new - 0 remove
21-07-25 15:29:32 INFO (MainThread) [supervisor.resolution.fixups.store_execute_remove] Remove invalid Store: d27bc1c4
21-07-25 15:29:32 INFO (MainThread) [supervisor.store.git] Removing custom add-on repository https://github.com/fondberg/spotcast

Now I see that there are warnings/errors in the Logs, but neither Google happens to find concrete Information nor are there any Issues openend in the Projects for this Issue.

Additional information

No response

home-assistant / supervisor