Ovulation confusion

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TTC baby number two from this month.

Have never been back on contraception since first baby - so since no longer breastfeeding my cycles have returned super regular. I haven’t done any ovulation tests before so I’m unsure what CD exactly I ovulate. But according to the app it’s around CD 15/16- However I know not to rely on the app for this. I’ve taken ovulation tests on CD 16 and 17 this month and both have been negative. I have no symptoms really of ovulation so should I just continue to test or is it likely I’ve missed my peak? My periods have always been regular being the last week of the month. Any advice appreciated!✨