Imported approx 20 contacts from a vcf file.
Remapped fine and the import appeared succesful
Clicked on Contacts tab and they appeared as cards (all good so far)
Click on the Mail tab and create new email - type in contacts name and they appear after the first few characters (excellent), I then cancelled the test email i was completing.
Now when i click back to the Contacts tab the contacts are all completely gone, page is blank and not a single contact to be seen or edited 
They still auto appear when typed into the recepient box but nowhere else.
Restarted multiple times, no difference.
Re imported and mapped and no difference
Contacts tab is blank
ps Using latest version downloaded direct.