Why do I get the message ..., multiple call attempts failed?

You will get this message when six or more calls have failed for a given communication interface (mobile telephony, VoIP or landline telephony). This alarm ensures that all dial-out capabilities are monitored.

Good to know:
1. an unaccepted or incorrectly accepted alarm is also considered a failed call attempt;
2. be aware when using voicemail. If the alarm call is not accepted before a certain time then it goes to voicemail. This is also considered a failed call attempt.

This is resolved as follows

The counter is reset to zero only when there has been another successful call over this communication interface.

See Alarms|System failures: Internal failures for further explanation.