I found seats departing PHL on Friday, February 1, returning from MIA on Monday, February 4. This seems to be the only weekend available at this price, but this fare is widely available for midweek departures.
Another option is to fly down one-way for $59, which is widely available for Friday and Saturday departures. Coming back is a little harder to find so you can try making a booking on a separate carrier for the return or try a nearby airport like Tampa (TPA).
American's Basic Economy fare includes a standard carry-on bag, but you'll have to accept a random seat assignment at check-in for this price. A Main Cabin Economy fare for the mentioned dates is $500+ roundtrip, so best to go with the Basic Economy offering in this instance.
Need a room in Fort Myers? Here's what's available for the mentioned weekend dates on Hotelwatchdog.
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