Hi,
The subscription name is not available out of the box in the logs. You will have to do something custom on your own if you want to have the subscription name. For example, this can be achieved by having some daily or hourly automation like azure function, logic app or azure automation runbook. That workflow can take the subscription ID and subscription name from your APIM instance and put it into its own table. You can use Log Ingestion API to insert data in Log Analytics.
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