I have the same problem as the user in the mentioned thread, but starting an EC2 instance (which I already had before) did not resolve the issue. I can only run 2 tasks concurrently in my ECS Fargate Cluster. The problem is, I don't really know which quota increase request I should choose. I tried Tasks per service but so far, I haven't got an answer. I am not sure, but I think there is a bug in the quota view because in the column Applied quota value every entry says Not available
Also, I had to select 5001 as quota (1 above default) which does not make sense to me because I cannot even launch 2 tasks.
Maybe someone can help me which this problem.