Available hours in Timesheets, under the "Review & Approve" tab, of the Modern UX, for a resource is being verified against "My Timesheet" view. In My Timesheet view it is shown correctly as 36 hours, as expected. But in the "Reivew & Approve" tab it is shown as 38.4 hours.
Availability field in Resource properties is set to 8 hours for this resource.
Change Availability - only if relevent - to 7.5 hours. There might be genuinue cases in which this should remain at 8 hours. Do not make any changes in such cases.