The data shapes would be enough.
I was just using some random shapes:
model.cuda()
x = torch.randn((200, 3087)).cuda()
mask = torch.randint(0, 2, (10, 3087)).cuda()
out = model(x, mask)

and could solve the device mismatch error by adapting the init_hidden method.
However, of course now a shape mismatch error is raised, as I don’t know the input shapes.