Hello, and welcome!
In the event that a passenger has lost picture identification, the TSA has a list of alternate ID's that are acceptable (shown below). If you don't have any of these other forms of ID, don't worry; you will be asked to fill out a form with your name and address. This will enable the TSA screener to search publicly available databases to verify your identity.
In addition, if this is your return trip and you already have shown your picture ID on the first leg of your trip, this information is on your side.
I don't believe you should have any problem boarding your flight, however, since you will need additional screening, make sure to arrive at the airport 2 hours before your flight departs.
I hope you enjoy a wonderful flight!
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