Hello,
I want to make a multilevel list like this:

-Tier 1 securities: Dial by A, B, ..
-securities Level 2: Dial by A.1, A.2 .., B.1, B.2 ....
-the Level 3 securities: Dial by A.1.1, A.1.2 .....

So I've created a new list, but the problem when dialing, I can have levels with the number 2 and so on ie (A.2, A.1.2, A.3. ..)?

T Are there a solution? I await your answers!
Thank you in advance!