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Yes, it is a scam / phishing mail.

See the following Apple articles: 

If you think your Apple ID has been compromised

If you think your Apple ID has been compromised - Apple Support

Recognize and avoid phishing messages, phony support calls, and other scams

Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support

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If you receive a suspicious email or SMS text message that looks like it's supposed to be from Apple, please email it to reportphishing@apple.com

How to report suspicious emails, messages, and calls

• If you receive a suspicious email that looks like it's supposed to be from Apple, please forward it to reportphishing@apple.com.1  
• To report a suspicious SMS text message that looks like it's supposed to be from Apple, take a screenshot of the message and email the screenshot to reportphishing@apple.com.
• To report spam or other suspicious emails that you receive in your iCloud.com, me.com, or mac.com Inbox, send them to abuse@icloud.com.
• To report spam or other suspicious messages that you receive through Messages, tap Report Junk under the message. You can also block unwanted messages and calls.
• Report scam phone calls to the Federal Trade Commission (U.S. only) at reportfraud.ftc.gov or to your local law enforcement agency.

After you reported, delete the message and see -> Clear the history and cookies from Safari on your iPhone, iPad, or iPod touch

Clear the history and cookies from Safari on your iPhone, iPad, or iPod touch - Apple Support

To keep your Apple ID account secure, see the following Apple articles:  

See who has access to your device or accounts

See who has access to your iPhone or iPad – Apple Support (UK)

Delete suspicious content from your devices -> Delete suspicious content from your devices – Apple Support (UK)

Check your Apple ID device list to see where you're signed in

Check your Apple ID device list to find where you're signed in - Apple Support

• if you see devices that don't belong to you, delete from your account.

Personal Safety User Guide -> Personal Safety User Guide – Apple Support (UK)

Manage and use your Apple ID ->Manage and use your Apple ID – Apple Support (UK)

Never jailbroken your iPhone.

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