She put a face mask made of honey on her face and some of it got into her mouth when she was fasting
There is nothing wrong with using honey on the face to remove freckles, soften the skin and so on, so long as there is no extravagance involved.
Shaykh Ibn ‘Uthaymeen (may Allaah have mercy on him) was asked: Some of my friends use eggs, honey and milk to treat freckles on the face. Is it permissible for them to do that?
He replied: It is well known that these things are foods that Allaah has created to nourish the body. If a person needs to use them for any other purpose that is not impure, such as a remedy, then there is nothing wrong with that, because Allaah says (interpretation of the meaning): “He it is Who created for you all that is on earth” [al-Baqarah 2:29]. The word lakum (for you) includes all beneficial uses, so long as there is nothing to indicate that it is haraam.
With regard to using it for cosmetic purposes, there are other materials which may be used for that purpose instead of this, so it is better to use those. It should be noted that there is nothing wrong with beautification, rather Allaah is Beautiful and loves beauty. But being so extravagant about it so that it becomes a person’s main concern and he thinks about nothing else, and neglects a lot of his spiritual and worldly interests for that, is not appropriate, because it comes under the heading of extravagance, and Allaah does not love extravagance. End quote from Fataawa al-Mar’ah, compiled by Muhammad al-Musnad (p. 238).
If the honey entered your mouth and you tasted it without swallowing, that does not affect your fast. It is permissible for the fasting person to taste food if need be, then spit it out without swallowing. See the answer to question no. 26837.
And Allaah knows best.