Hi, Veeramanikanta?
I had a similar issue, my name has four words. Sprint application only supports three words.
In last name if you type two words with a space, application doesn't proceed further. I removed the space and on next screen got name mismatch with pan. It asked me to take photo of pan and later card is approved after two weeks.
In your case, there's no solution but try entering the name up to 12 characters and continue in middle name field. The final screen will show pan name mismatch like what happened with me or if there's some issue leave the application as it is and some SBI card executive will call on mobile number, tell him to alter name as the character space is not sufficient.