Is it permissible to refrain from buying a mobile phone for an orphaned housemaid—who is 24 years old and considered like a daughter—despite her insistence, out of fear for her losing her money and misusing it, and is there any sin in that?

Preventing this orphaned girl from buying a mobile phone is the correct approach to safeguard her wealth, character, and religion. This is especially true since a phone can be a means of harm and corruption if it is in the hands of an irresponsible person. Averting harm takes precedence over gaining benefit, and there is no benefit for her in a mobile phone, as she can communicate through other means. We advise convincing the girl that this prohibition is for her own good, and raising her to obey Allah, perform religious obligations, and avoid prohibitions.