[update]
Hi everyone, I've solve this problem after my long research on Internet.
(For Mac, Taiwan user) Please find the following file, and change the name "zh-hant.mo" to "zh-TW.mo"

I guess it's the same way to solve for PC users and users from other countries or regions.
Hoping this info could help you!
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Plan
Premium
Country
Taiwan
Device
Macbook Pro 2017
Operating System
MacOS 11.1 (Big Sur )
My Question or Issue
Please take a look at the image I attached.
I've checked out most of solutions, and it's really a rare situation.
There's no any error content to identify what the problem is, and all I can do is to clean up & reinstall Spotify App (but still doesn't work).
Since I can still use the open.spotify.com to listen to musics, I think my account is fine. Does anyone knows what's going on here?
Hey there folks,
Once again thanks for waiting.
We can confirm this should now be fixed!
Make sure your device and operating system are up-to-date before trying again.
If you happen to experience the issue again, write in the Help Boards and let us know the exact Spotify version you are on as well as make and model of the device(s) involved.
We'll be keeping an eye out for your replies, thanks!