Residency Calculator Ineligible

Hey Guys,
I applied for my citizenship last week and received a letter stating that I do not meet the criteria of applying for naturalization. Looks like there was a gap of 8 days in 2015 between 2 gnib cards and I have to apply it again because of 8 days.
I called the immigration office and they recommended that I should just send this letter with the new application form filled out and another bank draft and leave all the supporting documents as they will take the documents from my old file.
Do you think I should reapply with everything or just send the application with a cover letter stating the reason? As they suggested if I do so I might get my draft back as everything else is already checked.
Thanks

I think you should do as they have suggested.
Also, did you not have any letters from Inis to cover the gap?

I just have the residency Calculator returned to me.

Well then you csn simply wait and send them the residency calculator with a cover note, I d say. Looks like they have given you s chance to reapply.