Error message: Unfortunately, the PIN is blocked. Please contact customer service (A3).
Solution:
Reset Mobile ID PIN: https://www.mobileid.ch/en/login
Instructions: https://trustservices.swisscom.com/hubfs/Website%20Files/Documents/Support%20Documents/English/Mobile+ID+Recovery+Code-en.pdf
Important:
Please use your Recovery Code otherwise a new registration (identification) will be necessary to use the Signing Service