My elevated button in flutter is not working, I can see it in the screen but does not react to the on Pressed function

Question

The button is intended to delete/dispose a voice message when you are recording a message and you lock the record but does not answer to onPressed function.

This is the code

  Widget timerLocked() {
    return Positioned(
      right: 0,
          child: GestureDetector(
            onTap: () async {
¡              timer?.cancel();
              timer = null;
              startTime = DateTime.now();
              recordDuration = "00:00";

              _stop();

              setState(() {
                isLocked = false;
              });
            },
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              mainAxisSize: MainAxisSize.max,
              children: [
                ElevatedButton(
                    onPressed: (){
                      print('this is not working');
                      dispose();
                      testColor = Colors.white;
                    },
                      child: Icon(
                        Icons.delete,
                        size: 24,
                        color: testColor,

                    )),
                Text(recordDuration),
                ),
              ],
            ),
          ),
    );
  }