I see no problem keeping "Lalla" since there is no equivalent in English that will fit this context.

The ref posted by Arabic & More posted here again
https://en.wikipedia.org/wiki/Lalla_(title)

shows this is an honorific probably something like Her Royal Highness (HRH) Princess Anne but clearly this is not going to work here in this context even if changing it to a direct Your Royal Highness as it is just too formal.

So I would keep Lalla with the name as in the examples given of royal wo,men in the reference. Irt migh be possiblew to aclarify she is a princess elsewhere in the text but it doesn'd fit here unless in line 20
Line 20 (as Phil has pointed out) needs to be changed from "oh dear" to Dearest (princess/one/lady), you have possessed our hearts (OR keep it present tense "possess our hearts")

and line 21 perhaps should be "heal" rather than "cure"?

Line 31 looks strange also.

I think someone who is fluent in both languages is needed here and certainly a native English speaker, conversant with the cultures of both source and target text audiences is needed to proof it all

Lyrics:
Dear] Lalla, Malika
The heart healer
00:11
Dear beauty
00:14
Oh dear lover
00:17
Dear Lalla, Malika
00:20
Oh dear, you have possessed [our] hearts.
00:23
And you cure them
00:26
Dear Lalla, my love is yours
00:29
Oh daughter of Moulay Idris
00:31
Who has a feather turban
....


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Note added at 1 day 5 hrs (2022-08-07 12:50:18 GMT)
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oops sorry! Text seems to have been skewed a bit:
wo,men in the reference. Irt migh be possiblew to aclarify she
should be
women in the reference. It might be possible to clarify she

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Note added at 3 days 15 hrs (2022-08-09 23:41:00 GMT) Post-grading
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Glad to help.