How can I find my phone

Here are some Find My iPhone documents that should help you figure out specifically what the problem is especially the fourth one.

Set up Find My iPhone https://support.apple.com/en-us/HT205362

If your iPhone, iPad, or iPod touch is lost or stolen https://support.apple.com/en-us/HT201472

Find My Phone - Lock and track your device using Lost Mode https://support.apple.com/guide/icloud/use-lost-mode-mmfc0f0165/icloud

If Find My iPhone is offline or not working https://support.apple.com/en-us/HT204233

I don't think so.

Some other articles you can look at.

Find My - locate offline device (2)

Find My - locate offline device (3)

Find My - locate offline device (4)

If it says “offline” then it has no internet connection. Without a live internet connection, it cannot be tracked remotely.