My iphone was stolen, it initially showed location but now it isnt under the find my iphone app

It won’t show anything after 24hrs in terms of location. In find my iPhone/iPad it should then just show as offline, but it should still be listed there as one of your tracked devices.

If it had been erased, the opposite of what you see should have happened - if erased it should still show as a listed device in find my iPhone in your iCloud account, but it should not show in trusted devices (erasing breaks the tracking feature of a lost or stolen device, but does not alter activation lock, and it removes the device from trusted devices so codes no longer go to it).

So honestly I’m not sure what may have happened. I cannot think of a scenario where it would disappear altogether from find my iPhone, yet remain listed in trusted devices. An erase should result in the opposite.

Having never actually used lost mode, I’m not familiar with the notification email. Since it was offline when you set lost mode, you should receive a message when it came back online and received and processed that command to enable lost mode. I’ve just never seen what those messages actually look like or contain. That one looks legit at least from the image.

One rule I stand by though is never, ever use the links embedded in any emails, from anyone even your most trusted service company’s or accounts. You already know the url to use for any of your online services and accounts, so just access them independent (as you normally access them) of any email or text received. Rigidly follow that simply rule and your chances of being a victim of a phishing spam plummet (that goes for bank emails, social media, shopping accounts - any and every internet account you access or use - never blindly trust any email or text with embedded links).

If it is not showing at all under the find my iPhone app nor under your trusted devices in your AppleID account settings

Sign in to iCloud - Apple and https://appleid.apple.com/

then someone who knows your AppleID and password has removed it. It can only be removed from either place if someone knows your AppleID and its password (and if 2FA is enabled, they’d need access to one of your trusted devices). Otherwise it should still be there but will show “offline” if it’s been disconnected from the internet for more than 24hrs.

If someone has your AppleID and has removed it, there is nothing you can do other than report the theft to the police and your carrier. You should also take steps to secure your AppleID as soon as possible (start by reading - If you think your Apple ID has been compromised - Apple Support).

If your iPhone, iPad, or iPod touch is lost or stolen - Apple Support

I would still change your AppleID password and enable 2FA (if you have not already set it up) if you can.

Two-factor authentication for Apple ID - Apple Support

Even if the thief erased the device, it should still remain under your tracked devices in the find app at www.icloud.com (and as long as it remains there it is activation locked). Erasing a device means it’s no longer trackable, but it should still show in your list of devices (which, as I say, indicates activation lock remains in effect).

Now even when I open the message it sent on my iPad it only shows me the location of the iPad I'm using.

What message are you referring to? Did you receive some type of message regarding your stolen device? If so, it is very possible that you fell for a phishing scheme that got you to log in with your iCloud ID and that allowed the thief to restore your device and turn off Find My iPhone.

Can you provide a screenshot of that particular message? Remember to redact any personal identifying information.

Had you clicked on a notification in Find My iPhone? That email looks legitimate, but it is difficult to tell with a photo. Did the device disappear from your iCloud shortly after receiving this email? If you hover over the view location button there, does it appear to point to an Apple page?