Problem with DATETIME column in MySQL

I have a table with a column defined as follows:

`Listing_Date` datetime DEFAULT NULL,

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Running the following queries return results normally:

select count(*) from caselaw.cases;
select count(*) from caselaw.cases where Listing_Date = '0000-00-00 00:00:00';

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However,

update caselaw.cases set Listing_Date = null where Listing_Date = '0000-00-00 00:00:00';

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returns the following error:

Error Code: 1292. Incorrect datetime value: '0000-00-00 00:00:00' for column 'Listing_Date' at row 1

How can I get rid of the '0000-00-00 00:00:00' values?