Hey!

The question you have asked lacks some details making it a bit vague. You haven't mentioned the name of the institution or the form. Anyhow, generally one is supposed to submit or upload the latest income certificate in case of admission related stuff and mostly when a candidate is applying through a quota. So, if you were asked to submit the income certificate of this year only and you had submitted the same, then it's fine. Whichever institution you are referring to in your question, must have provided details of submission of the income certificate, you may go through the details once for better clarity.