No, my friend, you have not done anything wrong I guess, don't worry you have been mistaken with numbers. The income should be less than 8 lakhs which is 8,00,000, not 80,000 what you have written is 1,50,000 which is 1 lakh 50 thousand which fulfills the criteria of eligibility for pmsss. In document verification, they will check that the income mentioned under the income certificate is less than 8 lakhs or not.
Also if you feel that there is something wrong with the income certificate then you can make another one or you can make an Affidavit for the correction. You can ask more questions here for any other query.