Is it permissible to swallow a small amount of toothpaste unintentionally while making up for missed fasts, even if it's at the time of the Fajr athan or its beginning?

If a fasting person swallows something unintentionally, their fast is not invalidated, whether this occurs at the beginning or end of the day, based on the Almighty’s saying: ﴿So fear Allah as much as you are able.﴾ [At-Taghabun:16]. The fast of this person is valid and no compensatory fast (qada’) is required of them. However, intentionally breaking the fast without a valid excuse during a compensatory fast is not permissible.