We can't know. You have not providedany useful info like system, version of AE, details about the composition and its settings and so on nor have you actually explained your problem. Sorry, just spitting bulletpoints is of no use to anyone.
If you are new to AE it's probably a workflow issue. We need to see a screenshot with all of the modified properties of your layer revealed. Do this by selecting the problem text layer, press the U key twice, print screen and then paste to the reply field on the forum. If you are on a Mac then Shift + Ctrl/Cmnd + 3 then drag the screenshot from the desktop to the forum.
Make sure that both the switches and modes column are shown in the timeline. If would also be a good idea to show us the modified properties of the camera layer.
If you suspect a bug or some fouled up settings first Reset your workspace or pick the Text workspace, close AE, open AE and start a new composition, make sure the view is set to "Active Camera," press Shift + Ctrl/Cmnd + t to add a new text layer in the center of the comp, reset the character panel (little icon at the top or the Character Panel) adjust the font size to make it bid enough to fill about 1/3 of the screen, type something, set the layer to 3D, set the layer to 3D and then press w to bring up the rotate tool and rotate the text on the Y axis. If this works then you have something fouled up in the comp that is giving you problems.
layer operates in 3D mode, all axes active. But not showing the effects in 3D. All settings are standard.
Didn't show us the switches and modes columns (second icon at the bottom of the timeline) but I figured it out anyway and you didn't show us the modified properties of your text layer (uu), but I figured it out anyway.
See the top right corner of your Composition Panel? It says Cinema 4 D as your rendering engine. Did you read the warnings when you switched to that rendering engine?
Unless you are using the features enabled with the C4D rendering engine like extruding text or shape layers or bending 3D layers you should be using the Classic 3D rendering engine.
If you must use the C4D renderer the work around complicated if you want to use the C4D rendering engine and extrude your text. It involves converting the text to a shape layer or pre-composing the text layer as a 2D layer and using that layer as a texture for your extruded text layer.
It's just not worth it. I'd just create the 3D text layer, export your AE comp as a C4D project, import the C4D project and extrude and texture the text layer using C4D lite that comes with AE. You'll have many more options, it will render faster, and, after you learn the technique, you will get a better product in a lot less time.
Thank you very much! Created a composition with classic 3D and the problem was solved!
Sorry for my stupid mistake, just started to learn the program =)