I had the same experience when calling the store number listed online. I called back a second time and connected with someone. I ordered a party pack of 10 tacos and received only 6. Sergio took care of the issue when I explained it to him. Good luck.
If it were me I would drive back to the store and personally demand that they give me what was owed. I would also request for them to offer me a discount or some free food for my inconvenience. If you're not wanting to do anything like that you could call another taco bell in the area and ask them if they can provide you with a phone number for you to call to settle your issue with the specific taco bell or maybe even higher up on the totem pole like corporate or something like that.
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