lost accents and quotation marks

Hello, my chromebook xe500c21, is allright but I can no longer put accents or quotation marks. If I hit the keys, just nothing happens.

This started about two weeks ago and I have a feeling that the cause may be this: I logged off and came back and then suddenly AGV started interfering when I wanted to browse on the internet, I unchecked it because I prefer to use Google.

Can you help me out?

kind greetings, sarneell@xs4all.nl