If you have a good understanding of English, it shouldn't matter that it isn't your first language.
When you're in hypnosis, your conscious mind tends to translate what Marisa says into your first language. You will find the same beneficial effect on you whichever language you find yourself connecting with during the hypnosis.
You don't need to worry and you will likely drift into better hypnosis as a result now that you are aware of this; whichever language you're hearing.
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