Why he stopped talking to me suddenly?

Okay so one week back we really had a great conversation on Facebook. He liked that so much nd even told me to come back soon and sent hearts emoji at the end. He was very happy with me but after one week when i texted him he didn’t reply nd till now he had not seen my message. He is not active on Facebook his activity status is I don’t know whether its off (intentionally) because he is coming online on other social media accounts.
Why he stopped talking to me suddenly?
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