Is it possible to get signed token or account creation more than 1 time by sending the same request?

[oliverdozsa]

First, I really like the idea of Stellot!

One question that I do not seem to understand is what prevents users from getting a signed token more than one time during vote casting? Or requesting to create more than one account by sending the same message and signature but with different voter public key? (I haven't tried these, just checked the code)