Is there an another way to get date instead of getting it from user’s device

I want to make an application that will only open at a specific date. I use new date() to do that, but new date() get time from the user’s device and the the user can open it by changing the time on its own device.

Example:

  let setdate = new Date('2021-12-10')
   let currentdate = new Date()
   console.log(setdate)
   if(setdate.getDate() == currentdate.getDate()){
    document.getElementById("result").style.display = 'revert'
   }

<div id=result style="display:none">Open now!!!</div>

If I don’t do anything with the time of my device, it won’t do anything. But if I change the date on my device to the specific date, then the area could open.

Could anyone suggests me a better way that could prevent this situation or is there an another way to get date instead of getting it from user’s device

Thanks for any responds!!!