1. How can something that disappeared tell you something?
2. "use key from network 10 or 13 key" is a very strange message. It seems to be unique: Google doesn't know it.
I'd visit the router management page from your browser (you need connection via an Ethernet-cable for that) and check or change the password.
My wifi network just disappeared 4 days ago it keeps telling me the network key has changed I enter password and it says use key from network 10 or 13 key it's a HP 15Notebook I am not tech savvy any help would be greatly appreciated thanks.

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