New field is not saving

Database field “published_on” is not updating in the database.

    App\Model\Entity\News Object
(
    [id] => 1
    [title] => What Is Blockchain technology .
    [description] => What you need to realize is that bitcoin is a currency, an electronic version of an asset, similar to gold. 
    [cover_image] => news/bitcoin-3089728_1920.jpg
    [is_approved] => yes
    [created_by] => 11
    [created_on] => Cake\I18n\FrozenTime Object
        (
            [time] => 2019-08-11T15:00:12+05:30
            [timezone] => Asia/Calcutta
            [fixedNowTime] => 
        )

[published_on] => 2019-08-12 02:03 04
[category] => India
[tags] => #whatisblockchain #howblockchainwork #Founderofbitcoin
[is_deleted] => 
[detail] => 
[[new]] => 
[[accessible]] => Array
    (
        [title] => 1
        [description] => 1
        [cover_image] => 1
        [is_approved] => 1
        [created_by] => 1
        [created_on] => 1
        [category] => 1
        [tags] => 1
        [published_on] => 1
    )

[[dirty]] => Array
    (
        [is_approved] => 1
        [published_on] => 1
    )

[[original]] => Array
    (
        [is_approved] => no
        [published_on] => 
    )

[[virtual]] => Array
    (
    )

[[hasErrors]] => 
[[errors]] => Array
    (
    )

[[invalid]] => Array
    (
    )

[[repository]] => News

)

Why no colon between the minutes and seconds?

You will need to delete all the files from following folder:
“your_app/tmp/cache/models/”
Then run again.

You have to check your entity of the table.

Consider, if you are using cakephp 3.*, then each table will have Entity and Table file in your Model.

Ex : users table in database
then Entity/User.php, Entity/UsersTable.php will be created if we run through cake bake.

If you have the User.php
Open the file and check the new field in the accessible function which you created