No HSTS header

Hello.
I enabled the HTTP strict transport option in the settings but when I wanted test it I got these results : https://hstspreload.org/?domain=justcook.co.il
My problem is similar to this ticket : https://ww.wp.xz.cn/support/topic/no-hsts-header-2/, but it was already resolved so I opened this one.
Thank you in advance.

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