Quick start Whatsapp

Hello. I just bought a new iPhone and decided to transfer my data using Quick Start. I could have chosen to transfer them via iCloud as well, but since I had little space on my old phone, I decided not to take the risk and opted for Quick Start. It did, in fact, restore everything—photos, browsing history, basically all my data, even apps running in the background. However, when I went to set up WhatsApp, I couldn't restore my chats. My friends told me that I just had to bring the phones close together and the chats would be restored. I was told that all I needed to do was open WhatsApp on the new phone and transfer the SIM card. I've been trying to transfer the chats for a day now, but it either gets stuck, gives me an error, or looks for old iCloud backups. Of course, once I remove the SIM card from one phone to put it in the other, WhatsApp won’t work on the old phone anymore because it needs the SIM. I've tried everything, and at this point, I think the only solution might be to return the phone if I really can't find any way to fix this