First diagnose your block. Half the problem of "block" is working out what is wrong. There are many reasons why you may not feel you are writing well, or being productive, or even writing at all.
What sort of block have you got? Perhaps you have loads of ideas but no idea how to get them on paper, in a viable form? This is accompanied by a sense of panic that you will never be able to achieve anything concrete.
Writing practice is the answer in the first instance. Set yourself small achievable goals to take those first baby steps. A daily page or two of writing, perhaps loosely based on one of your ideas, with the clear idea that this is just preparation work, not a potential Booker Prize winner. Writing out the ideas that interest you will help you explore them in more depth and make you see how they might be shaped into something more formal. Plus you will have the benefit of having actually written something which will reinforce your sense of purpose. Think of it as an apprenticeship. No writer can burst out fully formed with the first line he or she writes.
When you are at this beginning stage, it is perhaps best not to tell friends and loved ones what you are up to. They have a way of asking if you've finished anything yet or worse still "Written the bestseller yet?" This is not helpful when you are still learning to walk. So discretion is not a bad idea. Just keep filling up your notebooks. Then you will feel you are achieving something.
Do you feel instead that you have no ideas at all? Once again, small goals are in order. Do writing practice and exercises on set subjects so you don't have the worry of thinking up the topics. Again, don't be overly critical. Originality and brilliance don't matter. You are merely flexing your muscles to keep them in order.
In addition, make time to read, look at paintings, watch movies and be curious and attentive. Do something unaccustomed. Break your routine. Think of all these activities as deposits in your idea bank.
Keep the goals small again. Don't worry that you haven't come up with an idea for a Hollywood blockbuster. Think perhaps about creating one single character and then imagine the world around that character, and how that world affects the character in terms of goals, obstacles and outcomes. For example, put your character in prison and then wonder how he got there, how he feels about it and what he is going to do about it. You can write about this in your practice sessions.
Lastly, you may feel you have nothing left to say. This can be caused by having recently written so much that you are completely exhausted. Allow yourself a break. Relax. If you feel driven enough you could try a few exercises, really simple word games, like making lists of favorite words or doing something silly and enjoyable like writing limericks.