Valmiki Ramayana Kishkindha Kanda Sarga 53 Shloka 15

तेषाम् for them, मयस्य Maya's, मायाविहितम् created by his Maya, गिरिदुर्गम् impassable mountain, विचिन्वताम् while searching, यः such, राज्ञा by the king, समयः time set, कृतः was fixed, मासः month, व्यतिक्रान्तः exceeded.

While they were ransacking the impassable mountain created with the magical powers of Maya, the time limit of one month set by the king was over.