Spam calls are irrelevant messages sent over the mobile to a large number of recipients. The calls which are considered as the spam calls are telemarketing calls, robocalls, and scam calls.
These are the ways through which you can prevent spam or telemarketers call:-
1. Get on the do not call registry.
2. Call your phone company and request to block spam callers.
3. Install call blocking app on your cell phone through which you can block spam calls.
You can also prevent spam call with the help of reverse phone lookup service. If you want to know about reverse phone lookup service in details then just take a look at https://www.reverseasia.com/