Junior Alexander Guy, 49, got his first cell phone ever on May 7, the Orlando Sentinel reported.
Starting the day he got his phone, Guy received calls from people saying, "You murderer!" and, "You deserve to die!"
"At 2 o'clock, 3 o'clock in the morning I kept getting these," Guy said.
The next day, Guy said he realized that T-Mobile had given him the phone number formerly used by George Zimmerman, the Neighborhood Watch volunteer who fatally shot teenager Trayvon Martin in February.
The phone number was the one Zimmerman gave to a police dispatcher in a recorded call the night of the shooting. The recording has been made widely available to the public through news organizations and Internet.
During the nine days Guy had the number, he estimated he received about 70 threatening phone calls, CBS News reported.
"I was not only afraid for my life, I was afraid for my mother's," he said.
On May 16, Guy handed the phone over to his lawyer Robert Trimble who asked T-Mobile to pay damages. T-Mobile denied the request, but offered to change the number on Thursday.
T-Mobile spokesman Glenn Zacarra said the company has retired the number and provided Guy an account credit and waived an early termination fee.
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