I have been using the free version of TrueCaller for some time, but it was not very effective in my area (I live in Europe). Spam filtering databases tend to be more or less effective depending on specific coverage, and that may vary significantly between geographical areas.
I have eventually settled with Hiya (https://apps.apple.com/us/app/hiya-spam-phone-call-blocker/id986999874) as that proven to filter almost every unwanted call I receive. My suggestion is to test different apps and find the one that works better, as there is no silver bullet.