I was using windows wallet which
hello@nikko.io is v1202.
But when I opened it after long time, it did not sync.
So, I removed file appdata/roaming/Unifyv2 except for wallet.dat, and then I downloaded v1203 and opened it.
As a result, wallet balance became 0, but transaction which I recieved coins remains.
How can I restore my coins?
If you have an old back up of your wallet.dat aside from the one in the Unifyv2 folder, try to use it. I had the same problem before of not showing the real balance after syncing but transactions is still recorded and using an old back up solved it. Removing files and installing the new wallet did not help me (tried several times).