If repairing the Google Contacts now shows no contacts under your eM Client Gmail account (which is very strange), then “go online to your Google Contacts and see if they are there”, as the repair just re-syncs your online contacts to eM Client and clears out the old local contacts cache.
So “if your Google contacts are showing online ok” but no longer in eM Client, then i would next either go to “Menu / Accounts” and remove and re-add your Gmail account using the automatic account wizard which should then automatically bring all your Google contacts back.
Alternatively if you have been making regular eM Client backups either automatically via the Settings or manually via the menu, then you could restore a recent dated backup when you know your contacts were there and any new emails etc will sync when eM Client connects again.