I don't really believe in writer's block.
People in other jobs such as say, plumbers or builders or teachers or doctors don't get plumbers block or doctor's block - so why should writers?
I think what people mean is that the writing experience in that moment isn't easy and fun. But if it's your job then that's no reason not to do it anyway, even if it is tough. Imagine if the Doctor said, "I'm sorry, I can't do your operation today, I've got Doctor's block" (ie; I don't really feel like doing it) - you wouldn't rate him very highly as a Doctor, would you?
Writing is simply the act of putting words down one after the other. If you think you've got writer's block then just start writing. Unless you have some physically crippling disease, there's no reason why you shouldn't be able to do it. It may not be good writing but you won't have writer's block anymore.
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All the best to you! Write!