I am getting everything right but I got regular time wrong for all months. Help me pls.

Plan production for a four-month period: February through May, For February and March, you should produce to exact demand forecast. For April and May, you should use overtime and inventory with a stable workforce, stable means that the number of workers needed for March will be held constant through May. However, government constraints put a maximum of 5,000 hours of overtime labor per month in April and May (zero overtime in February and March). If demand exceeds supply, then backorders occur. There are 80 workers on January 31. You are given the following demand forecast: February, 81,408; March, 61,440; April, 100,000; May 40,000. Productivity is four units per worker hour , eight hours per day, 24 days per month. Assume zero inventory on February 1. Costs are: hiring, $45 per new worker, layoff , $65 per worker laid off; inventory holding, $10 per unit-month; regular time labor, $10 per hour, overtime, $15 per hour, backorder, $20 per unit. Develop a production plan and calculate the total cost of this plan. Note: Assume any layoffs occur at beginning of next month. (Leave the cells blank, whenever zero (0) is required. Negative values should be indicated by a minus sign. Round your answers to the nearest whole number.) February 81,408 0 + Forecast Beginning inventory Production required Production hours required Regular workforce Regular production Overtime hours Overtime production Total production Ending inventory Ending backorders Workers hired Workers laid off 81 408 20,352 106 81,408 0 March 61.440 0 61.440 15,360 80 61.440 0 61 440 0 May 40,000 -18,560 58,560 14,640 80 61.440 April 100,000 0 100.000 25,000 80 61.440 5,000 20,000 81.4401 18,560 0 0 0 81,408 0 0 26 0 61.440 2.880 0 0 0 0 26 0 0 Regular time Overtime Inventory Backorder Hiring Layoff Total February March April May $ 192,000 $ 192,000 $ 192,000 $ 192,000 + 0 0 75,000 0 0 0 28,800 0 0 371,200 0 1,170 0 0 0 0 1,690 0 $ 193,170 $ 193,690 $ 638,200 $ 220,800 $ 1,245,860 Total cost