There are folk that demand to get read notices and for this, I fear messaging apps are falling short because there is a push for PRIVACY. Demanding that an app tell you that the message was sent, received, read and what time each step occurs borders on privacy intrusion. An example is that my email system ignores read receipts and blocks a few common tracking methods.
So for your question you need to hit Whatsapp support but my answer is to believe the person you are conversing with. Give them the benefit of doubt here. Why not?
I have been using whatsapp for like 8 months to talk to someone who lives in Europe and I live in the USA. When that person travels to another country and has to change out their simcard/number, they claim they have no access to their whatsapp since they don't want to migrate their account to a new card that they are going to be using for a small amount of time. Sometimes I send messages to that person on whatsapp while they are in another country (besides their own) traveling and I am unaware they are away. When I send said message, the 2 grey checks show up and then they turn blue, so I assume the message is read. However, when said person returns to their own country from traveling and swaps out their sim card/number back to their regular one, they claim that they are just then seeing the messages. So my question is this...why do the check marks turn blue before they are actually read. Is this true that they don't see them till they go back to their normal number/sim or am I being lied to. I have never traveled overseas so I dont know how these things work The only thing I DO know is that when you travel overseas, you need either a new phone, a new simcard if your phone allows that type of thing, or a temporary number. Please help me as I am really confused about this and I am not Easily confused...I normally know what is going on, pretty smart with tech and stuff, just not sure about this since I don't really travel and the person I am referring to does travel quite a bit. Any help/info would be GREATLY appreciated.

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