Skanda Purana 7.20.232

7.20.232

pratigrahānantaraṃ vāmanasya padatrayārthaṃ vikramaṇam . tad dṛṣṭvā daityānāṃ trivikramasyopari śastrāstrairākramaṇam . devadānavayuddham, daityānāṃ parājayaḥ, brahmaṇā baleḥ samayakaraṇam . devānāṃ rājyaprāptiḥ, baleḥ pātālapraveśaḥ, devaiḥ kṛto vāmanastutiḥ . devānāṃ stutyā saṃjātatoṣātiśayasya vāmanarūpasya viṣṇoḥ svābhimānato yogabhraṃśaḥ . yogabhraṣṭe tasmin tadantareṇāsurīpāpmāyāḥ praveśaḥ . tatkṛtā ca viṣṇościrantanī vāmanarūpatāpattiḥ .

After receiving the gift, Vāmana's striding forth to measure the three paces. Seeing this, the attack of the daityas against Trivikrama with weapons and missiles. The war between the gods and dānavas; the defeat of the daityas; Brahmā's agreement with Bali. The gods regain their sovereignty; Bali's entry into Pātāla; the praise of Vāmana uttered by the gods. Because of the excessive delight born of the praise of the gods, Viṣṇu in the form of Vāmana falls from yoga due to his self-conceit. As he fell from yoga, the demonic sin entered him through that [gap]. And through that, Viṣṇu came to retain the form of Vāmana permanently.