Welcome to Microsoft Q&A! Thanks for posting the question.
Azure Application Insights has not been migrated over to the new Q&A platform. We kindly request you to post your question on MSDN forum here to receive support from the right set of audience. Thank you for your understanding.
I wish to help you set in the right direction with this issue & I understand you have mentioned that the alert only works the first time, the following checks are worth a try:
The log alert is triggered only after the data is available, please review the fail requests.
Review the Action Rule alerts for actions & conditions/time period or overlapping rules again.
Review for any suppress alert configuration/scope.
We cannot completely understand your question as this is an English global support. It would
be helpful, if you can translate the configuration options/alerting rules that you have set in English while posting on MSDN, it would be very beneficial to understand the problem much better.
Apologies for any frustration with this, we are actively working to onboard remaining Azure services on Microsoft Q&A. We will make a public announcement once complete. You can also see the Microsoft Q&A supported products/forums on the [right-side]. Want to Learn more about new platform: Microsoft Q&A Getting Started
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