Daylight Savings Fall Back Hour Not Paid

Location: Texas I work overnight for a State-run institution. We are being told that even though we worked 9 hours, we will only be getting paid for 8 hours worked. The reasoning in our policies is that we get the hour back during the spring forward part of DST. However, I checked and I did not get that hour last year and won’t this upcoming year since I don’t work on those days. Is this legal?