The user authorises all in-app purchases through the Google Play Store and you can cancel your Truecaller Premium subscription at any time from the Play Store.
Steps to cancel on Android: refer
Learn more here: refer
NOTE:- We give all users a trial period on the first purchase only and during that period you can cancel the purchase without being charged. After that period, no refunds are made.
Exceptions wherein cancellation for the premium plan is not allowed:
1. Gold plan (refer)
2. Prepaid or One-time Subscription purchased (refer)
3. If you have converted your current subscription into a higher plan (Ex: Yearly Premium to Family Plan or Yearly premium to Assistant Plan)
4. If you have exhausted the trial period, a refund is not eligible.