The message explicitly describe the problem:
You can only ask 50 questions in a 30-day period.
There's a limit for how many questions you are allowed to ask within 30-days (1 month), probably in order to limit spam or help vampires. I suggest you to wait until the next week or month and try again.
50 questions per month is quite a large number though.
Apparently this was indeed a problem because the user never posted a single question. This problem is caused by the usage of a public IP. The only known solution is to use a proxy.