I just tried it and got this error:

Code request failed. Reason: too frequent attempts to request the code
You can retry requesting code after 1 hour(s) 36 minute(s)

Should I retry later? Is there a risk that my account gets banned due to too many registration attempts?

As I wrote, I was using Yappari until yesterday under the same number with no issues (worked great on my N900, thanks to Scorpius!).