Answered by: Maulana Irfan Ali
I combed my wet hair during fasting in Ramadan and then felt that somehow a few drops of water got into my mouth. I thought about what to do for a moment and then just swallowed normally. Maybe it was 2-3 drops at most. I swallowed on purpose, but I had no intention of breaking my fast and I don’t know what to do now and how or if water got into my mouth. It felt like the maybe 2 drops mixed with the saliva in my mouth.
بِسْمِ اللهِ الرَّحْمنِ الرَّحِيْم
In the name of Allah, the Most Gracious, the Most Merciful
If the water was swallowed, be it a drop or two, on purpose, this invalidates the fast which will require one fast.
Only Allah knows best
Written by Maulana Irfan Ali
Checked and approved by Mufti Mohammed Tosir Miah
Darul Ifta Birmingham
 Fatawaa Mahmoodiyah page 163 vol 15 Maktabah Mahmoodiyah