iphone 16e Calender can't sync with any accounts: icloud, gmail....

I just got my new iphone 16e device yesterday, it synced well at first but suddenly my calendar can't sync with my mac calendar any more ( I'm sure the 2 devices are using same accound ). Weirdly, my old iphone 13 mini syncs well with my mac

This is what my mac calendar looks as I mainly add schedule on it and also in google calendar shown in celeste.

This is what my iphone looks like:

1) It can't sync with iCloud due to internet connect problem

2) I tried to add delete my google account and add again but it said that my account is already there, but it doesn't.

I've tried the methods on my iphone 16e below but none of them works:

1) Sign out my Apple Account and sign in again

2) Turn off my iCloud Calendar and turn it on

3) Delete Calendar app and download it again

4) Delete my gmail account when I found it couldn't sync, but I am not able to add it now

[Edited by Moderator]