Hello when i use vault in my 1.20.1 server chicken egg is empty how can i fix this??

It is quite possible that another plugin causes this issue, that is a plugin does something you did not expect - however that interaction is only performed when Vault is present. I'd look at all permission and economy-related plugins.

However, I am afraid that your query could easily be misunderstood: It lacks the necessary details and it seems you have not yet developed a profound grasp of the English language. Both of these points can be mitigated by simply writing more: adding more context, writing what the expected behavior is, what the actual behavior is or attaching screenshots and/or videos.