Your name should be entered as mentioned in your 10th certificate. So if you have filled according to the 10th certificate you won't face any problem. If you haven't done as per 10th certificate you cannot change anything because the correction window last date has passed.
There is not a major issue if you have not filled your surname in the candidate name. When you appear for exam, you will have to explain to the invigilator (if (s)he ask for the particular thing when matching the credentials with your ID Card), that you made a mistake and didn't fill out the surname in the application form.
But take precaution from the next time whenever filling any application form.
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