I have a Toyota Yaris 1.3 from year 2000. Yesterday I was unable to unlock my driver door - the key won't turn (either direction). The key works on the passenger's side. It's not frozen, temperatures are well above 0 Celsius (32 Fahrenheit).
I read somewhere that Graphite spray can help in this situation:
Some of the people advised to use WD-40.
Is it safe to use them?
What else could I try?