You might have had your IP changed. go to www.ip-chicken.com and if that IP is different than your old one you have a dynamic IP.
it's odd that it changed after over a year, usually it's much more frequent.
The IP you would have gotten though ipconfig /all is your internal IP. Anyone outside of your network can't use it. it looks like 192.168.x.x or 10.x.x.x.
I'm not quite sure why this is happening. Maybe do some googling?
Do you have the forwarding rules also forwarded in your firewall? If not, you should add a rule for the port you are hosting the server on (defualt is 25565).
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it's odd that it changed after over a year, usually it's much more frequent.
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I'm not quite sure why this is happening. Maybe do some googling?
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