Do you have extra nodes saved in %appdata%roaming/Gameunits/Gameunits.dat file or something like that?
Add this node 47.36.138.25:1338 to config and restart the client.
Even this not working.
Then it must be your computer or router, check your configuration.
Previously, it used to work, but not now. In fact, I have other coins which are staking okay but not this one. I think in order to work for me, some extra nodes are needed, as I have found people having problems with other coins not staking, with them needing extra nodes for successful connection or staking. I think only dev can solve this problem. Otherwise, my coins will be stuck forever in wallet.