Another way to decrypt Matthias' crypted words

Hello everybody! This is another way to decrypt Matthias' crypted words. Before I start, i want you to tell me in the coments if i made any mistakes!

So, lets say we have: 3LC - 3MC - 3NA - 3DB

First, eliminate every number: LC-MC-NA-DB

Now, the first letter LC;

LC:

L is the 12th letter of the alphabet

C is 3rd letter of the alphabet

3+12-1=14

The 14th letter of the alphabet is N

MC:

M is the 13th

C is the 3rd

13+3-1=15

15th letter is O

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.

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And so on.

Now, can you tell me what dose this mean?

(HB) (AA)-(KC) (ID)-(UA)-(JB)-(AF).

Have a nice day! Good bye!