Internal error, no drug ID specified! plus onsite/in-house drug inventory not updating

I followed all instructions including activating Pharmacy Dispensary Module. I added all the drugs in the inventory and made sure all the templates are completed. When I attempt to prescribe drugs to patient, everything appears to work fine, template auto-populates as expected. When I click “Save and Dispense”. Then I get hit with this popup message “Internal error, no drug ID specified!.”

The drug gets added in patient’s prescription and medication list as requested but the in-house onsite inventory is not getting updated by deducting whatever drug prescribed and dispensed. I followed all instructions in the Pharmacy_Dispensary_Module. I made sure

OpenEMR Version
I’m using OpenEMR version - V6.0.0

I’m using: chrome

Operating System
I’m using: AWS Cloud Express - through personal windows computer

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