What do you do when you can not solve basic things? I am a phd student in math. I am studying abroad. I need some advice.

When i started my Phd, my supervisor gave me a book and she(my superviosr) asked me to study it. In the first year, i passed 5 courses. Then, i thought, maybe that is good time to ask her(my superviosr) to give me a question. 

She gave a question at once. Even, she did not think about it. I worked on it in several weeks, then i found out it follows from some paper. 

She gave me another question. She did not think about it again. I workd on it several monthes but i could not move it. She gave another question from another area. I spent some monthes to read about it. Whenever i asked a question from her, she asked some basic question from me, sometimes i could not give answer to them. Then, when i came back home, i regreted a lot why i can not give answer. 

I felt, i lost my self confidence. During of this time, i was studying a area that i liked and i was getting pretty good on it. In fact, i watched some lectures about it on youtube that helps me a lot. She gave me another question from another area. I spent some monthes to read about it, then she told me , she could not work with me and she wasted her time. That was big shock for me. I am working with my master superviosr.

I still have some problems. I lost my self confidence and there is a fear in body. When i am studying, i am scared a lot. I checked every thing many times . For instance, i check what is countable set. 

She never helps me. All of my colleagues have been either taught ot given idea by their superviosors. She told me, i did not know any things, she told me, how i passed bachelor and master. On the other hand, she told me, i am good the area that i worked alone. I have passed all of my courses.  But, i am not good like before. I am really scared. That is so difficult to explain it.

I need to mentioned i have passed all of my courses during of PhD. This semster, i have a course but i was not good in the course at all, as i lost my self confidence.

I would like to be good mathemacian, but now i can not even calculate geometric series. I do not know how it happens that i can work in PhD but i can not solve basic things. I am scared to ask my colleages, even though, i ask here. Do you know all of basic things? Is it big problem sometimes we forgot basic things?  Baisc things means that things, we learnt in Bachelor.

What would you do in this situation?

Thanks in advance.
I'll give two bits of advice. Both may be hard to do. The first is to relax. Some things in mathematics are just very difficult. The experiences you have had with the material itself seem completely normal to me. 

But the second is to try to find a more compatible and helpful advisor. Your advisor may not be bad, but seems ill suited to help you with what you need. 

I can't judge your math background, of course, but if you can pass graduate courses it must be ok at least. Maybe excellent. 

Your inability to solve basic problems may be overstated. It may just be "brain freeze" based on your emotional state. It may be that you are better suited for longer reflection rather than quick answers. But, until you learn to relax you may continue to have problems. Many people use periodic physical exercise to help them relax and give their mind a rest from work. But perhaps you need something. You might even need to talk to a counsellor. 

I think my own advisor was helpful, but day-to-day I worked on my own. He gave me problems to work on. The first was too easy, so no real challenge. The second was too hard, so no progress. The third was just right, though it still took a year to but the thesis together. I was lucky in a sense that I went through my low period before I met him and so had bounced back and was able to be more productive. But a low period is pretty normal for math doctoral students.