SMS sent without my consent from my Redmi 7A phone? I hope this question is on-topic here. I am completely puzzled at this. On 26-Feb-2020 at 4.24 PM IST an unknown SMS has been sent from my Redmi 7A Android Phone without my consent to a completely unknown number.

See the attached screenshot for the message contents (it starts with ACTA and then contains some encoded data). It's all either encrypted or garbage. I have no clue what this is and I can not infer anything from this.

All apps before installation are scanned by built in security check. I have run security scan on my phone and nothing suspicious found except need to update MIUI.  No app was installed on that day and I do not download any unknown apk's from unknown sites. All apps have always been installed from Google Play Store.

The number does not exist in my contact list and has never ever been dialed from or any call received on this phone. Could someone explain this? Any clarification on what this could have been would be great to know.

Truecaller site reports that number as a spam number from India.

Thanks.
According to quick research, the "ACTA" SMS is used by ICICI Bank for a verification/activation message on their mobile apps (e.g. iMobile).

From Mi Community - Unable to activate icici i-mobile app on my POCOFONE F1,


  Post #10 
  
  Solved after the solution given by the online imobile team.
  During the activation process,  you get some random text message (ACTA *** which need to be sent for verification) , you copy the entire text and send the same to 9215676766 instead of +91222208888 (icici server number which is usually busy).
  This sms need to be sent within 90 seconds and jump back to imobile app and proceed with the activation by setting 4 digit pin and grid value verification. [...]
  
  (Emphasis added)


Also, thanks to the OP for confirming it on the comment thread,


  I then called ICICI Bank customer care and the representative has confirmed that this number (ed. +9184220...) belongs to their iMobile servers and the message is some kind of legit verification message required by the app to function properly. Earlier I must have clicked 'Allow this app to send SMS' so the whole process happened automatically.