I reset my Iphone SE(2016). It asked for passcode, now it is disabled

Issue : Iphone SE is displaying the message - iPhone is disabled. Connect to iTunes. However iTunes does not connect / detect the phone

Details :

1. I had upgraded my Iphone SE 1st generation to 2nd generation.
2. After that, I reset the SE(first generation).
3. However, I did not remove it from the cloud.
4. I restarted it to set it up as a new phone for my mother.
5. it asked for passcode, 4 digit. However my passcode was 6 digit.
6. I tired all possible combinations I had used in the past.
7. It now displays the message - disabled, connect to itunes.
8. iTunes does not detect the phone because i had never synced it with itunes in the past.
9. I have now removed it from my iCloud
10. I am still unable to use it.
11. I have tried holding sleep/wake button & home and sleep/wake button and volume down to hard reset. but it is not working.

Please advise what to do!