For that to work, you will need a SIM card from the region you are changing CSC to.

It's just you; close the tab and start again.

The official one UI 7 has not yet been released; only the beta version was released in Germany, the US, the UK, India, and South Korea. It will officially be released in other countries after the upcoming Galaxy Unpacked event tomorrow. We will proba...

The best way is to use SamFw Tool software for Windows. There are a lot of videos on YouTube and articles online that explain the whole procedure.

Sorry to hear that. I always have the same problem with my Buds 2 Pro; resetting them, as I mentioned above, always fixes it. Maybe someone else will offer a solution; also, try searching online.