There are income limitations on the stimulus payments and this could have reduced your payment(s) .
Families earning less than $150,000 a year and individuals earning less than $75,000 a year should get the full $1,400 per person. Families earning up to $160,000 per year and individuals earning up to $80,000 per year will receive prorated stimulus checks for less than $1,400 max.
-follow this link for a handy stimulus calculator-
Third Stimulus Check Calculator, Check if You're ... - TurboTax
