Is there any way to get the last location of my iphone when it’s offline

Only if it was updated to the latest iOS and you allowed that setting -> iCloud - Find My - Apple

”You can even find devices that are offline.

If your missing device can’t connect to the internet, the Find My app can still help you track it down using the Find My network — hundreds of millions of iPhone, iPad, and Mac devices around the world. Nearby devices securely send the location of your missing device to iCloud, then you can see where it is in the Find My app. It’s all anonymous and encrypted to protect everyone’s privacy.“

No. Offline is offline. Past 24 hours, Find My no longer has any location info, if that last location info is (was) available.