At what block number? Try restarting the wallet if you didn't already. If that doesn't help and the wallet shows that you have more than a few connections, then click to go to Tools - Information - and click the "delete local blockchain folders" button to let it resync.

Also currently uploading a blockchain snapshot file for faster syncing. This will be available at https://www.bitc2.org/snapshot-march-29-2019.zip after a couple of hours. If you choose to use that instead of the in-wallet resync button, read the ReadMe.txt first.