BBT help

Ilean • Mon, Feb 10

Hi everyone I have been charting my BBT this is my first time charting and OPKs I took my temp this morning at 3am usually I do it at 5am but woke at 3 am today. My temp said 97.80 I then took it again at 3:05 and said 97.75 which temp should I use? And is 97.80 even a temperature 🤒 charting number?