Cannot see "last seen" on WhatsApp?

[Owen]

Some people on whatsapp don't have a "last seen" when they're offline, they literally have nothing at all!
But when they are online, it shows "online" and I can still chat with them, which means I did not get blocked, so how come I couldn't see their "last seen"s?

If you are gonna tell me about the Last Seen Timestamp (OFF/ON) option on iOS, I have already tried that and all it does is to disallow me from seeing EVERYONE'S "last seen".
So if I (ON) that option, EVERYONE basically has no "last seen"s.

So how come some people have no "last seen"s even if didn't block me? I don't want to ask them either because it'll be awkward. If you know the reason please tell me. Thanks.

[Olivia]

i have answered this in your other question. its because they turned off their last seen timestamp too...