C4D to AE Object Buffer ID

Hi!

[Sorry for my approximative english :)]

In C4D, I have a 3D render with two Object buffer ID. No Alpha Channel.
Then, i import my 3D render in After Effects and I apply the two Object Buffer ID :

- Layer 1 : my_3d_render + Object_Buffer_ID_1 (with Luma Matte)
- Layer 2 : my_3d_render + Object_Buffer_ID_2 (with Luma Matte)

Its works well, but when I enable the Alpha channel in After Effect wieport, I see a transparency area at the itersection of the two Object Buffer ID.

Do you know how can I fix it ? To obtain a clean Mattes compositing.

The image below show you my problem.

Thank you very much for your help!

Anthony