mi note 11 continuous reboot issue

If your phone is in warranty get it checked with service center. This could be software issue or hardware issue as well. Check if It's volume up button remain in pressed position. If not resolved factory reset the phone or flash software if your phone bootloader is unlocked.

Known issue with Xiaomi phones. (Corrupt software/app : Phone bootloops everytime it tries to load apps & services post reboot)

First get into recovery (Power + Volume Up) / fastboot mode (Power + Volume Down) and check the bootloop status. If the phone remains stable, then go with "Data Wipe" via Mi Recovery and it should fix the issue (Unfortunately there's no way to backup your pictures and other data unless you already got the bootloader unlocked)

Never take a note series phone... Its all half baked phones... That is why they overhype that phone... And create a virtual hype... People and retailers buy it in dozens in flash sales... There is no quality control for these series.... I have used 4 note series phones... All I have to sell in 6-9 months due to some issue or other...... Due to these hypes.. They have good exchange rates... So have always got more money in exchange than the price bought I it..... That is the only advantage of note series.... Rest phones. Of xiaomi.. All worked good...