1. **Make sure that your Exchange account is configured correctly on your mobile devices.** Go to Settings > Accounts & Passwords on your iPhone or iPad and make sure that your Exchange account is listed. If it is not, you will need to add it.
2. **Check your Exchange server settings.** Log in to your Exchange server webmail interface and check the settings for your email account. Make sure that the "Sync email signatures" option is enabled.
3. **Update your Exchange account on your mobile devices.** Go to Settings > Accounts & Passwords on your iPhone or iPad and tap on your Exchange account. Then, tap on "Update Account."
4. **Restart your mobile devices.** This will help to refresh the connection between your devices and your Exchange server.
5. **Recreate your email signatures on your mobile devices.** If the above steps do not work, you may need to recreate your email signatures on your mobile devices. To do this, open the Mail app on your iPhone or iPad and go to Settings > Signature. Then, tap on "Create New Signature" and enter your desired signature.
**I hope these solutions help you resolve your issue.**
**Additional tips:**
* Make sure that you are using the same email signature on all of your devices.
* If you are using a complex email signature with images or formatting, it may not sync properly to your mobile devices. Try using a simpler signature.
* If you are still having problems, you can contact your Exchange administrator for help.
