I used zebra linkos sdk in our app but when i want to release it apple rejected it because of "Not in MFI Program"
all they said is
We are unable to post your app to the App Store at this time because your app has not been authorized by the accessory manufacturer to work with the MFi accessory:
Please contact the accessory manufacturer to request your app be added to the MFi Product Plan form.
Once the accessory manufacturer confirms that your app has been added to the MFi Product Plan form, please reply to this message. When we receive your reply with this confirmation, we can proceed with the review; we do not require a new binary even though your application state in iTunes Connect state is Rejected.
If you have not yet provided the accessory's MFi Product Plan ID (PPID), please enter this information in the Notes section for your app in iTunes Connect. If you do not know the PPID, please request this information from the accessory manufacturer.
Thank you for reaching out to us. If your app connects an iOS device to a Zebra MFi product via Bluetooth and you plan to distribute your app via the B2B or standard App Store, then you must register your app with Zebra in a process known as white listing, otherwise Apple will reject your app submission (which is what happened per Apple's email).
Please view this page for details on the white listing process and how to get that process started with Zebra.