Is Yogmaya Lakshmi or Parvati? Give reference from authentic scriptures.

 Yogamāyā is Mahālakṣmī. She is the eternal consort of Lord Nārāyaṇa (Viṣṇu). She is the covering and connecting power of the Lord who perfectly perfectly controls and arranges His divine pastimes i.e his līlās.

Adhyātma Rāmāyaṇa (Ayodhyā Kāṇḍa, 5th Sarga):

"This Rāma is the supreme Viṣṇu, remembered as the primeval Nārāyaṇa; and this Jānakī is that very Lakṣmī, renowned as Yogamāyā."

Jānakī Kavaca (from the Brahma Saṃhitā): Sītā is again praised as the Supreme Parāśakti and Yogamāyā who sports with Lord Rāma:

"Jānakī, the Māheśvarī, the Parāśakti, is known as Yogamāyā. She, Sītā who assumes various forms, sports in the companionship of Rāma."

Bṛhad Viṣṇu Purāṇa:

"Victory to you, O Mahāmāyā! Victory to you who destroy the sufferings of devotees! Victory to you, O Goddess beloved of Viṣṇu! O Yogamāyā, I bow to you." (Here she is called Viṣṇupriyā).

Lakṣmī Tantra:

"As I connect (link), so I am known as Yoga or Yogamāyā; as I confer knowledge on men, so I am known as Māyāyogā."

Skanda Mahāpurāṇa (Maheśvara Khaṇḍa, Kedāra Khaṇḍa):

"O Yogamāyā, O Yogeśvarī, full of youthful beauty, bearer of the pair of Śrī and fruit of union, O Goddess Lakṣmī, obeisance to you."

When Śrī Kṛṣṇa performs the Rāsa dance, the texts say He "takes refuge in Yogamāyā." Vaiṣṇava Ācāryas clarify that this Yogamāyā is none other than Śrī Rādhā:

"Here, the term Yogamāyā refers to two powers: The supreme power (paramā-śakti) and The covering power (āvarikā-śakti). The supreme power here is Śrī Rādhā herself in her role as the presiding goddess of the Rāsa-līlā."

-Gopala Tapani Upanishad Commentaries

Yogamāyā is Mahālakṣmī (and her expansions like Sītā and Rādhā). She is the conscious, dynamic Svarūpa-śakti of Lord Viṣṇu.

Jai Vaiṣṇavī Mā!