I have 10$ but icant buy

Again, have you contacted iTunes Support? If not, do so, as no one here can correct the issue.

You will need to follow the instructions in the message, and contact iTunes support. Use the link below to do so.

iTunes Store - Contact Us - Official Apple Support

you should contact Apple about this, it may be an account issue. This is the community support forum

Have you contacted iTunes Support as instructed? What was their response?