The grey chat box and "tap to chat" message on Snapchat indicate that the person you've messaged has not yet opened your message. This feature is designed to let you know that your message has been delivered but not yet viewed by the recipient. Once they open the message, the chat box should return to its normal color, and you'll be able to continue your conversation.
Here are a few possible reasons why the chat box turned grey and displays "tap to chat":
Unread Message: The person you've messaged has not yet opened your message, which is why the chat box appears grey and prompts you to tap to chat [1].
Pending Delivery: The message you sent is still in the process of being delivered to the recipient's device. Until it is successfully delivered, the chat box will remain grey [1].
Connection Issues: If there are connectivity problems between your device and the recipient's device, it may cause delays in message delivery. In such cases, the chat box may turn grey until the message is successfully delivered [1].
Message Ignored: It is also possible that the recipient has intentionally chosen not to open or respond to your message. In this case, the chat box will remain grey until they decide to engage with it [1].
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