Excel formula to calaculate business hours between 2 dates

Hello Sir,
Can someone help in correcting the below formula as this not working properly when end time is greater than start time

=(NETWORKDAYS(start date,End date)-1)*("19:30"-"10:00")+IF(NETWORKDAYS(End date,End date),MEDIAN(MOD(End date,1),"19:30"-"10:00"),"19:30")-MEDIAN(NETWORKDAYS(start date,start date)*MOD(start date,1),"19:30"-"10:00")

Deva