CUDA free memory fail.

Accelerated Computing CUDA CUDA Programming and Performance
#1

I do this:

cublasStatus status = cublasFree(_devData);
		
if (status != CUBLAS_STATUS_SUCCESS)
	{
		cout << status << endl;
			
	}

I get status equals to 14 when meet free memory error. What number 14 indicate and what the real issue is?