In Gaudiya Vaishnav philosophy, Tulsi Maharani is not a Jivatma at all. She is a manifestation of Krsna's Swarupa Shakti (because she is an amsa of Radharani). This is because, Tulsi is an expansion of Vrndadevi who is one of the gopis of Vrndavana. Being a manifestation of Swarupa Shakti, She therefore possesses the powers of Parabrahman Sri Krsna (such as the ability to manifest into multiple bodies but retain Her identity).Tulsi specifically is described as the eyes and ears of Vrndadevi.
In Brahma vaivarta Purana it is described that when Lord Narayana descended into the form of the Shaligram Shila, Vrnda devi also descended in the form of the plant Tulsi to serve Him. She is not Jiva Tattva, but Shakti Tattva.
In the commentary to Srimad Bhagavatam, verse 10.39.53-55 (where Lord Krsna's potentiates are mentioned), Srila Vishwanatha Cakravarti gives the following commentary:
Sri is the potency of wealth; Pushti that of strength; Gir, knowledge; Kanti, beauty; Kirti, fame; and Tushti, renunciation. These are the Lord's six opulences. Ila is His bhu-sakti, also known as sandhini, the internal potency of whom the element earth is an expansion. Urja is His internal potency for performing pastimes; she expands as the tulasi plant in this world. Vidya and Avidya [knowledge and ignorance] are external potencies who cause the living entities' liberation and bondage, respectively. Sakti is His internal pleasure potency, hladini, and Maya is an internal potency who is the basis of Vidya and Avidya. The word ca implies the presence of the Lord's marginal energy, the jiva-sakti, who is subordinate to Maya. Lord Vishnu was being served by all these personified potencies.
In the 7th verse of His Vrndashtakam, Vishwanatha Cakravarti Thakur also says a similar thing:
tvam kirttyase satvata-tantra-vidbhir
lilabhidhana kila krsna-saktih
tavaiva murtis tulasi nr-loke
vrnde! numaste caranaravindam
Oh Vrinda! Highly qualified sages, who are well-versed in the Tantras of the mode of pure Goodness (the scriptures written by the Lord's pure devotees), have praised you as being the personified energy of Lord Krishna known as lila-sakti (the energy that helps perform His pastimes). You are also very famous in this world for your appearance here in the form of the tree known as Srimati Tulasi Devi. Therefore we offer our most respectful obeisances unto your beautiful lotus feet."
So in conclusion, Tulsi Maharani is not Jiva Tattva, but Shakti Tattva. Shakti Tattva, can manifest in multiple bodies with one identity.