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WaterGEM the System Head is lower than the pump curve settings

I am updating an existing water system model for a city with about 20,000 population.  I am having two problems. I have searched the Bentley Community forum, but I have not be able to fix the two problems listed below. I'd appreciate the advice from expertise.

1. There are four pumps pumps at higher flow rate outside the pump curve due to low system head (see the attached 'User Notification' and 'Pump Result').

2. Fire flow test results were computed to calibrate the model. The difference between the actual and model result of the static pressure are greater than 5 psi (between 4-6 psi.)(The residual reading difference between the actual fire flow test and the model results are 2-4 psi.)

Following is a list of updates that have been made:

1. Imported new piping, wells, pumps, storage tanks using Model Builder from AutoCAD. All pipe's C-values were updated based on the construction years.

2. Update pump curves for new pumps

3. Realized that the elevations near the river banks do not match with an USGS map. Imported elevation using TRex, then subtracted 8' using Global Edit in Junction Flex Table. Made sure the elevation of pumps, wells, and tanks remained the same.

4. Added the hydrants where the fire flow tests were conducted. Set the elevations of the hydrants to be 9.25' above the watermain

Please let me know if I should provide more data.  Thank you in advance for reviewing my questions.

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