Have you tried restarting Electrum client? I had this issue last night and I did this to solve it.
Otherwise, uncheck "Select Server Automatically" from the network and choose a different server. If it doesn't work, you can go to File>Open>Default_wallet and it should reload the wallet.
Yes, I have already tried restarting the client a few times but it didn't work. I have unchecked that option, and I have reloaded the wallet file, but still didn't affect. Otherwise, uncheck "Select Server Automatically" from the network and choose a different server. If it doesn't work, you can go to File>Open>Default_wallet and it should reload the wallet.
