As everyone stated don't mail this person.
What spell are you trying to do? The spell could be a dud [could be asking for something not magickally possible or require items that don't work in that particular spell] you might not be charging energy, you might not be focused. Once you've cast do you work for the goal or do you sit back and wait? These are common reasons why a spell would bit work. They are also very easily remedied.
What is the spell in question? We might be able to help figure out if it's working or not.
You might want to try some basic energy work to get a feel for the energy used in spell casting. Meditation can also help you focus and prevent your mind from wandering. Also, you might want to semi-memorize the spell before casting because if you keep stopping to find your place you're loosing concentration and can be effecting the spell, weakening the energy you're charging.