It does take about 48-72 hours. Since you've had no dial tone is your phone still connected to the plug in on the wall or is it connected the phone plug in on the back of your modem?
Call customer service, they can try and help then send you to tech support if it doesn't work.
It can take up to 48 hours for them to actually get the new phone line working. Sometimes it takes less time. You can always call the customer service number and have them look into it I dont think going into the store is going to help much unless you have no other way to call places. Good luck!
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