message: Fix invalid private balance
diff: @@ -74,7 +74,7 @@ size_t WalletModel::countPrivateCoins(CAmount &amount) const
  auto coins = zwalletMain->GetTracker().ListLelantusMints(true, true, false);
  for (auto const &c : coins) {
  - if (chainActive.Height() - c.nHeight + 1 >= ZC_MINT_CONFIRMATIONS) {
  + if (c.nHeight > 0 && chainActive.Height() - c.nHeight + 1 >= ZC_MINT_CONFIRMATIONS) {
  count++;
  amount += c.amount;
  }
  