Jangan worry sangat la, some babies memang ambil masa sikit untuk settle dengan tummy time, my friend's baby was the same, muntah sikit-sikit lepas minum so dia kurang enthusiastic nak prone. Kalau dia dah tunjuk dia boleh (dua kali tu dah bagus!) mungkin dia just need more low-pressure tummy time je, macam letak dia atas chest you or on a padded mat sambil you main dengan dia, bukan force sgt. Jangan over-stimulate, better observe jer dia explore at her own pace, some days dia lebih lazy, tu normal, bukan sign something's wrong. Since she's at 5 months soon, boleh la mention to your paed next checkup so they can assess if there's anything, tapi from what you describe sounds like she's just being a baby yang prefer her own timing!