Thanks Franco. It is the second. Gatekeepers are blocking assistance provided. So which one to use please?It depends if you mean: Assistance by the gatekeepers is being blocked, the gatekeepers are assisting with (the) blocking (of something) or the gatekeepers are blocking "assistance".
Hi Parla. Yes, i meant exactly what you wrote in your last sentence (highlighted in Red) Assistance is being provided by someone (agency) to the poor and the gatekeepers (who are employed by the agency to facilitate the process) are blocking the assistance. So they are preventing the poor from accessing assistance. So which sub-heading would be better: "Blocking of Assistance by Gatekeepers" or "Blocking Assistance by Gatekeepers".Welcome to the forum, Aimannz.
Your answer to Franco-filly wasn't clear, at least to me. Her second possibility was that people were blocking something, and the gatekeepers were assisting them. But your answer seems to suggest that assistance was being provided by someone and the gatekeepers were blocking that assistance.
Perhaps it will help if you can give us more context. Who was blocking what, exactly? Where? Exactly what what were the gatekeepers doing? (And what were they the gatekeepers of?)