How I can get new SMS on number, which I get earlier?
Then number keeps in base(during 1 day) you can get new SMS. You can do it in direction "history".
Why I can't get a number?
Because,a few numbers in base, but many people, who want to get numbers. Is formed live queue.
How much times one number can be used?
One number can be used for one service only once.
Then, why I enter number for sone service, and he says, that this number using now?
Because, numbers can be reissued. For example: Someone bought SIM-card, register on this number some service and end using this service. After 3 month SIM-card was deactivated and now, any can be get this number. But service using this number yet.
Which services I can use for add funds?
You can use this service now: Paypal, Bitcoin, Webmoney, Yandex money, Credit card.