It seems like there was an error in the payment system of SoF and I got my payment now. I tried to contact with the site Admin and they just solved my problem with the payment. Thank you very much for solving my problem, SOF Admin. :)
Today I gave at least 5 tutorials. I put a lot of effort into them. I offered them to the people asking questions with the lowest price. But what was the result? I don't know why they did not buy my tutorials. They just buy other works with higher prices, even if I finished questions much more quickly than other tutors.
It's ridiculous and sad!