Robocalling and number spoofing

The most common spoof though is same phone number except the last 4 digits. So I put a tasker rule on my phone to drop any phone number matching mine with a wildcard for the last 4 digits. I have another rule that sends any number that is not on my contact list straight to voicemail.

T-mobile has actually gotten better at detecting spam and spoof calls. About 80% of the spam I get now easily identified as they inject something like "scam likely" as the caller ID. I made another tasker rule with caller ID string matching so those get dropped as well.

Lastly, I play the disconnected number tones at the beginning of my voicemail message. This causes the majority of spam to drop the call and keep my voicemail clean. So now pretty much all I get is rare second or two long voicemail with nothing on it.
Lastly, I play the disconnected number tones at the beginning of my voicemail message.

What?? Please enlighten me.

OTOH, I found the best cure for nuisance phone calls is to change my phone number. I changed from Telus (mobile) and Shaw (land line) to Koodo for both and haven't had one nuisance call in the last 4 or 5 months. YEAH!
Come to think of it, nobody calls me. YEAH x2
What?? Please enlighten me.

When you record your "leave a message at the tone" or whatever voice mail greeting, record just the disconnection dtmf tones at the very beginning, and then record your regular intended message. Just about all automated and robo calling software detect these tones. It drops the call and marks your number as disconnected. These automated call services have a limited amount of ports/lines they can use at a time to dial out to a victim, so keeping lines available by dropping bad numbers is a priority.

Outbound caller ID is set by the originating phone system, so no. It should be as simple as the carrier blocking calls where your outbound caller ID number is one not associated with your account.
It was getting really bad for a while, was getting 3-5 a day for a couple months last summer. It's calmed down since then. When it started becoming a daily thing and I just happen to be in front of the computer, I would stick my phone in front of the speaker and play this for them, very loudly.


I got sick of doing that everyday, so I installed an app "Calls Blocker" from XDA and it's blocked pretty much all spam calls, and what does manage to get through Google Fi handles the rest by marking them as spam.