and I know enough about Amazigh, because the Amazigh community in Catalonia is important and their speakers have specific problems when learning Catalan or Spanish. Funnily, I have one of the few copies of the Catalan-Amazigh dictionary La llengua rifenya - Tutlayt tarifiyt
, by Abdelghani El Molghy et al. (and I know personally Mr. El Molghy).
Since you seem to be specially obtuse and deniing facts, I will resume here the facts, for clarity:
1. The name is spelled áíáì in Arabic. The spelling is the same in all the Arabic speaking countries.
2. The Arabic language is commonly written without vowels, which can be added as marks in order to clarify and fix the correct pronunciation (as in the case of the Quran, for instance).
3. The classical Arabic and the Modern Standard Arabic (MSA) have three and only three vocalic sounds: [a], [i] and [u].
4. The vocalic sounds [e] and [o] appear in some Arabic dialects.
5. Because of 3. (and 4.), in MSA the only possible diphtong is [aj] (commonly represented in figurated English spelling as Y) and not [ej] (commonly representend in figurated English spelling as AY).
6. In Arabic, there are dialectal differences in the pronunciation of words and names. ãÑíã, MRYM, is pronounced [ma'rjam] in MSA but [me'rjem] in Moroccan Arabic.
7. When writting in Latin alphabet, the spelling reflects the conventions from the language of reception: äæÑ, NWR ['nur] is transcripted as Noor in English, Nour in French and Nur in Italian/Spanish/Catalan...
8. The Arabic name ['lajla] has been commonly transcripted as Layla or Laila.
9. The Arabic name ['lajla] has been adapted in Persian as ['lejla], commonly transcripted as Leyla or Leila.
10. In Modern English, the group AY is read [ej] instead of [aj] (day, may).
11. Because of 10., in Modern English, the spelling Layla is read ['lejla].
12. When using English figurated spelling for pronunciations, LY is usually used to represent [laj] and LAY is usually used to represent [lej], by consistence with day/may and my/by and other common words in English.
13. When speaking about Arabic pronunciation, if there is nothing specified, that means MSA, which only has 3 vocalic sounds (see 3.).
14. The OP asked for the correct pronunciation of Layla in Arabic: LAY-la (['lejla], see 12.) or LY-la (['lajla], see 12.).
15. Since the OP didn't specified, that means the correct MSA pronunciation of Layla (see 13.).
16. The only possible correct MSA pronunciation for Layla is ['lajla] (see 3.).
17. The figurated English spelling to represent ['lajla] between the two options offered by the OP is LY-la (see 12. and 14.).
18. Someone who says "the pronunciation [of Arabic words and names] is the same whenever you go" lacks absolutely knowledge of Arabic language (see all the entries for dialectal Arabic in Wikipedia, for instance) or language in general (and the concepts of dialectal variation).
19. In Al-Hoceima the Amazigh is spoken (in the Tarifit variant), but it also is the Arabic (one of my former students is precisely from Al-Hoceima and lives there). To deny the existence of Arabic speaking people from Al-Hoceima is a) ignorance or b) a lie.
Before to say to others that they have to learn more about languages, maybe you have to apply this sentence to yourself and to learn a bit of IPA and basical linguistic concepts (as dialect, variation, standard, allophone, etc.).
Please, don't use terms as "sweetie" when discussing facts with other posters. It is absolutely disrespectful and this one is not the first time to use such words in this board.