How do I postpone my period?

Laura • 29 years old 💗 TTC baby #1 with my best friend and the love of my life 👶🏼

AF was supposed to start today, but it hasn't and I used to be able to just click a button that said "my period is late" and it would just postpone it, but I can't see it anywhere anymore. Anyone got an idea where I can find it? I can't edit future dates, so I can't set it for say 2 days from now.