Query regarding SSC Application Form filling

It is better always to fill all the columns which are relevant to the candidate. In the application form, there may be some mandatory particulars that will be required to be filled. One should not miss those details. If there are some columns that are not mandatory, you may skip them. Your application will not get rejected.
When we are filling such important applications we should not be in a hurry. Even if we see the instructions, it is clearly mentioned that once you have submitted your application you can't edit it. That is why before submitting we should go through the application carefully and do the corrections if required. Then only we should submit our application.
What I suggest you do is fill in another application and give all the details and again pay the fees. That will ensure that your application will not get rejected and you will definitely get the admit card for the test. That is the best option.
It all depends on the nature of the column you have not filled.

Whenever you fill up any application form related to a job, you need to be careful and ensure that you have responded all the queries entered in the form. Any slackness in this regard would lead to your disqualification for your consideration for the said post.
Sometimes you may notice some notification appearing in the advertisement that there is no scope for editing your application once you have filled up the same.
The only step in this regard would be to fill up the fresh application furnishing all the relevant details in your application form and verify the same cautiously if it contains any flaws in respect of filling up the application form. This is applicable in case the closing date of entertaining of application form is still not closed.

If that particular field is not mandatory one then I do not think that the application would be rejected. Generally, nowadays, if you do not fill a mandatory field then a prompt comes on screen to alert that the applicant has to fill it otherwise the application process would not move ahead. Do you remember such a thing happening when you filled the application form? Anyway if it did not happen then in all probability your application was completed and has been submitted. Now you concentrate in your preparation and studies for your exam and other related things and if they ask you to give that information at the time of document verification or counselling then you can very well provide it at that point of time.

You should be very careful while filling any form, if for any reason you forget the entry in any section, then you should review the form two to three times before submitting it, this precaution will be useful to you in the future, so keep these points always. Keep in mind that more care is needed in filling special offline forms because in online forms when any field is left blank, the system can give you an error, if that field is mandatory then the system will never accept the submission. You did not tell in your question whether you filled the form online or offline, apart from this, whether any last date was given for correction, if so, then you should see the notification once again if the process of correction is given with the last date Then follow him. If you are unable to get the correction done in both ways then you should contact the related department or board where you have submitted your form and ask for the correction.