Hello.
Same problem here. I have rebooted the computer and the electrum 100 times, hand-picked servers, run the wallet on another computer. Re-installed the wallet. Interestingly, I have other wallets on electrum, but only one of them does not work. All others are synchronized without problems. My friends don't have a problem with wallets either, just me.
Do you have the standard number of Electrum addresses on a standard wallet?
Is your wallet 2FA or did you increase the gap?
Are you using the LATEST version of Electrum (3.3.4) and download it from the official Electrum page? (
https://electrum.org/#download)