Replace value in a field type date

I need some advice to solve the following error.

I have imported a table from csv.

Some row contain the error showed above.  It is not an import error since the original document  does not contain any date in that field.

I expected NULL.

I have tried Replace Value in the Query Editor.

If I put "00.00.0000" as Value to Find the string is not reconigned.

Then I tried to change the type data from datetime to text but wihtouth success.

Could someone help me?

Thanks in advance.