If the wrong dates are used when entering FBT in Attache then the amounts won't show in Attache Online - Single Touch Payroll.
Most importantly the Pay Date in the Check Pays screen must be March 31st or earlier to show for this financial year. If this was entered as a later date, then it will not show and will be included in the next financial year.
If this was done in error, you will need to Reverse a processed FBT pay. entries using the wrong dates and re-enter correctly.
Another reason why some employees FBT amounts might not be seen in Attache Online is that they fall under the FBT reportable threshold. More details can be found in the article Process reportable fringe benefits payments.