A lot of transparent overlaid planes deactivated transparency

Dear friends,
I just do 2D animation and found the limit of 10 overlaid planes with transparent texture. If I add more than 10, transparent parts become black.
(I did it using the function “Import” > “Images as Planes” with checked alpha channel)
Could you please advice me how can I increase this limit?

Some vital information missing from your post
No demo blend file supplied for review
No indication to what renderer you are using
If using the default render then what type of transparency are you using (Z Transparency or Raytrace transparanecy)
If you are using raytrace transparency then increase the depth setting in the transparency settings

Bl or cycles

in cycles you need to increase number la bounces for tranps mat
in render panel

happy cl

It is almost definitely the max tranparent bounces, increase the number.

Hello friends,
thank you very much, it works!
Yes it was in Cycles