If you haven't signed out then according to Check your Apple ID device list to find where you're signed in - Apple Support
"If you're still signed in with your Apple ID on the device, it might reappear on your account page the next time your device connects to the Internet. To permanently remove the device from your account page, sign out of iCloud, iTunes & App Stores, iMessage, FaceTime, and Game Center on that device, or erase that device."
The only problem is if you do erase your device and you remove it from your account then according to Apple's various support articles, a thief will then be able to use the device.
Read this support article about what to do if a iPhone or iPad is lost or stolen -->
Find your lost iPhone or iPad with Find My - Apple Support
- The Find My service described in the article is the only recovery feature Apple offers. It must be set up before the device is lost.
- Note that if you remotely erase your device as instructed in this article, if you subsequently remove it from your account as in this article --> Check your Apple ID device list to find where you're signed in - Apple Support , then according to this article --> How to remove Activation Lock - Apple Support you remove activation lock from the device. That means if it was stolen, the a finder or thief then has a working device that can be used by another person.