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T-Mobile has sent its top engineers to Dallas to fix with the city calls a life-threatening problem with its mobile phones.

The T-Mobile 911 glitch started last fall, but they’re taking a harder look at the issue after the death of a 6-month-old boy Saturday night. There are questions about whether 911 delays contributed to his death.

Brandon Alex died over the weekend after his babysitter couldn’t reach anyone through 911. At the time, there was a spike in calls because T-Mobile phones were making “ghost calls” to 911.  She blames T-Mobile’s problem for his death. City officials say it is something they are trying to get to the bottom of.

"Why my son have to be the example? Why do I have to be the one to stand up and talk for everyone?" said Bridget Alex, Brandon's mom. "This is not what I want to be doing. I want to be at home playing with my son. But at the end of the day, he's gone and nothing can bring him back."

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The city said after a caller hangs up, their phone for some reason mysteriously keeps calling and overwhelms the 911 center. The problem only happens with T-Mobile phones.

The baby’s caregiver was using a T-Mobile device, but police are still investigating whether his death was directly linked to the problem. A medical examiner will determine his exact cause of death.

Dallas city leaders and T-Mobile representatives addressed the issue in a Wednesday press conference.

Dallas Mayor Mike Rawlings called the situation very frustrating and the city manager says he takes full responsibility for what's going on at the call center.

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