Torch.cuda.is_available() is false with cuda 10.2

I try to get GPU support on pytorch working. I can use cuda 10.2 and python 3.6 but with: pip3 install torch torchvision torchaudio it´s not working… What can I do? Also I could use cuda 11, cuda11.1, 11.2, 11.4 and 11.5.
thanks in advance!