What must she do if she applied transparent nail polish while she was menstruating and forgot to remove it from her feet after becoming pure for five days, and during this period she slept with her husband and performed ghusl twice?

The presence of a barrier on the nails invalidates the obligatory ablution (ghusl (definition)) for menstruation or janabah (definition). It must be removed, its place washed, and the prayers performed before it with incomplete purity must be re-offered. There is no need to repeat the entire ghusl because continuity (muwalat) is not obligatory therein. If the barrier is removed during the ghusl, the ghusl is valid, but the prayers that preceded the janabah remain [to be made up].