This is a very common warning message to display in your servers console, especially with newer game-versions such as 1.16+ , as well as modded servers. Unfortunately, there is no way to remove this warning as such, however, you can change two little things that will mean it does not affect the performance of your server, as for most users they will experience some lag due to this.
How to fix?
1.Click File manager, then click 'Server.properties'
2.Change the following fields:
max-tick=time=60000 to max-tick-time=-1
view-distance=10 to view-distance=4
3.Once done, click Save at the bottom, then restart the server! You should notice an immediate difference.
Still facing issues? Please create a support ticket and a member of our support team will investigate this for you!