Attention
Unexpected error occurred. We apologize for the inconvenience. If this error persists, please reach out to our support team [here]
If you want to inspect logs, you can [dffLogs do not contain sensitive information, and it would be helpful to attach them to problem reports to help the team investigate the issue you are experiencing.
Just use another litewallet like Typhon or Eternl in the meantime.
If you want to reliably get support, you may want to contact Yoroi’s support itself. The link that you quoted should point to https://yoroi-wallet.com/support, not to this forum.
If you rather want people here to maybe help you, you’d have to give some more information, e.g., the logs that are mentioned in that error message. Without, we cannot guess what the problem might be.
Hello,
The Yoroi team is already looking into it. It works fine for me. But some users encounter an error with the latest v5.9.0.
Its nice to see actually a person from Emurgo responding here. Keep it up. 
Thank you all!