Minecraft server connection problems

What do I do if my router IP has changed and I can no longer access my Minecraft server publicly? I have been helped on here before and we ended up finding the correct IP for my to connect externally but now no one can connect to the server externally and it looks like my router IP has been changed and the new router IP isnt working. I have used what is my IP . com to find my IP but that public didnt work. My port is 100% open and it was working until my router ip changed.