I've been using WhatsApp with my best friend for years and he swapped his prepaid simcard (old phone with with number = X) with a new prepaid simcard (new phone with number Y) lately. When he sent me the first message using the new phone with number Y, I received a new chat window because his number Y was not registered on my phone contact's list. When getting this new chat, I blocked the number because unknown to me. When he gave his new number Y, I added it to his contact record on my phone but chats didn't merge together and this is not what I had expected...because now I have our former chat window + the new one.
How can I merge the 2 chat windows together and keep only the one with the whole chat/calls/medias history?
Thank you, Bruno