Cannot read properties of null (reading 'value') from document.getElementById

I wish to read the value of this input field.

<input type="text" name="acadp_fields[1200]" class="text" placeholder="" value="December 26, 1969">

My code is this.

document.getElementById("acadp-upload-file-ipfs").addEventListener("click", function(event) {
    event.preventDefault()

    document.getElementById("acadp-upload-file-ipfs").removeAttribute("href");

    document.getElementById("loading").innerHTML = '<div class="acadp-spinner"></div>';

    const dateOfBirth = document.getElementById('acadp_fields[1200]').value;

    ...
    ...

But I’m getting the error below when I click the element acadp-upload-file-ipfs

Uncaught TypeError: Cannot read properties of null (reading 'value')

What am I doing wrong?

>Solution :

Try This

document.getElementsByName("acadp_fields[1200]")[0].value