Trying to conceive

My menses is regular, I use flo app to track, every single month my menses will happen on the day that flo predicted, if not one day after the prediction. Use ovalution test kit but still not successful. Had my first child within first try. Gave birth in sep 2022. Tried for second kid for about 7months now and still no news. Not sure why, very demoralised. Will be 35 years old next year.