I used this wallet for signing
https://drive.google.com/open?id=0B-5Ax5kejTpMLVdaVUNjZVpmZDQ.
But when the vote came this error. Signature not accepted. Either it is invalid or your HOdlcoin address (HDowSCdWojQWnvodyBzEwMk5n2br89j6kc) is empty. In fact, I have another wallet address HPxUhpdCaXS8tAKvyp7v3bh2KNmyakXY7v, what's the problem?
Best guess would be that the statement may have been incorrect - missing a character, or having an extra space at the end - something like that. What was the exact statement you signed?
Also, what's the signature produced, and the URL you're submitting at?