I recently changed host, so the ip of my server posted is old, is there any way to change the ip without having to remove it?

This is why we have a Guides and FAQs section.
(also linked in my posting 'signature' below)

See: How do I migrate player stats or rank between server pages?

In short: no, you cannot simply change the IP address of a server.
Some people opt for the dns option to retain their stats and rank.

However, if this is your old server: https://www.gametracker.com/server_info/50.31.103.70:25565/ then I would suggest that it is unlikely to be worth the trouble of managing a dns host name.