Cant blame him.
Scammer and con man have been running around without much consequences.
Just look at all the scams around.

Walk around town / mall -scammer approach you.
Sit in the house - scammer call you pretend to be court, police, etc.
Online selling platform - scammer whatsapp you.
Everywhere is scam and there is no active measurement to catch and penalize them.

Sometime police stop you also, you cant be sure it real or not.
If you ask too much, then kena label kurang ajar.

Even mintak tabung also got scammer - the other video where the person was asked about prayers and couldnt answer.

So it is common to be was was berwaspada when someone coming to your house.