Why my mobile sends SMS to a random number without my permission?

My mobile sends SMS to random numbers without my permission. All messages are sent automatically. Here is an example of an SMS.

SBIUPI qUrXgeX26iEY%2B2si9JHhubIjm7R2aHoo6pWcbXBpJho%3D

All the receivers are Indian numbers (mostly airtel sim card). When I check the Truecaller app I found those numbers are named Cybercrime Frauds and reported as spam by more than 18000 peoples.

I have checked my app SMS permissions and checked for hidden apps. I couldn’t find anything harmful.

Is there anything to afraid?