There are almost always some slight differences in totals between the Invoice (which is an aggregation of total approved TimeCards) and any WorkSegment report. These differences, however, should never amount to more than .001% of the total.
The difference is due to the rounding of individual WorkSegments to 2-decimal places. During the week, individual WorkSegments are stored. WorkRecords stores them to 4-decimal places and then displays them to a rounded 2 decimals. WorkSegment reports always round the individual segment and then aggregate the total segments. When those 7 days of segments are approved to create a TimeCard (to comply with federal wage laws regarding overtime), each un-rounded WorkSegment is added together for the worker over the 7-day period and then the total is rounded to the nearest 2 decimal places.
It's like trying to divide the number 1 into 3 parts and then adding the 3 parts back together again. It's never going to nicely add back up to the whole number 1.
If the difference in your invoice is more than .001% of the total, please contact WorkRecords Support by creating a Support Ticket and provide the Invoice number.