The recommended N amount seems wrong, What should I check?

Check that the “days to the next fertilization event” are accurate. Each new fertilization event has a default value of 10 days that must be modified by the user to reflect the actual fertilizer application interval. A vegetable field that receives 2 sidedress applications may have a fertilizer interval in the range of 12 to 15 days while a field fertigated through the drip system may have an interval of 5 to 7 days.
Check that the soil nitrate value seems reasonable. If the value is unusually high or low then you may want to resample the soil. Sampling immediately after a nitrogen fertilizer application may result in a high value.
Check that the maximum N uptake amount for the crop is reasonable. This value can be modified in the planting summary page.
Check that the start and end dates of the crop are accurate. The N uptake curve for the planting is affected by the planting and end crop dates.