From Wiktionary, the free dictionary
نَجَمْتُمْ • (najamtum) (form I) /na.d͡ʒam.tum/
- second-person masculine plural past active of نَجَمَ (najama)
نَجَّمْتُمْ • (najjamtum) (form II) /nad͡ʒ.d͡ʒam.tum/
- second-person masculine plural past active of نَجَّمَ (najjama)