Tag not monitored by Microsoft.
Do not call that number. This is almost certainly a phishing or tech support scam.
Azure Monitor does not send “unauthorized charge” alerts asking you to call a random phone number, especially to a personal email account that is not associated with an Azure subscription. Scammers commonly send fake security or billing alerts to create urgency and trick people into calling a number where they will attempt to steal personal information, credit card details, or remote access to your computer.
Legitimate Microsoft or Azure billing notifications will direct you to sign in to your official Microsoft account through the normal website, not by calling a phone number in the email. If you are concerned, open a new browser window and manually type https://account.microsoft.com or https://portal.azure.com and check your account there. Do not click any links in the suspicious email.
You should delete the email or mark it as phishing.
If the above response helps answer your question, remember to "Accept Answer" so that others in the community facing similar issues can easily find the solution. Your contribution is highly appreciated.