Need to input code on a webpage after clicking checkbox

[vikas0903]

Hi All,
I am trying to tick a checkbox and input code in text box appearing after that. URL is:
https://www.dillards.com/webapp/wcs...D1QyDu6J3CC1j4g==&ddkey=https:RememberMeLogon

[[if it asks user name passwords, please use vikas_manit@rediffmail.com & Abc1234. It's a dummy account.]

I am able to tick the checkbox but not able to input code in text box appearing below that. My code is :
'*********'ticking checkbok
IEapp.document.getElementById("giftCardSelect").Click
While IEapp.Busy
Wend
Do While IEapp.ReadyState <> 4
DoEvents
Loop
Sleep (10000)
'********************entering value

For Each myEL In IEapp.document.all
If myEL.ID = "gc-id" Then
'ActiveWorkbook.Activate
'Sheets("Sheet2").Select
i = 0
While i < myEL.Length
If myEL(i).Name = "giftCertificate" Then
myEL(i).value = "43745332"
End If
i = i + 1
Wend
Exit For
End If
Next
'************

Please help me in figuring out how to fix this error.

Relevant html code is given below:
<div class="gc-form">
<div class="gift-card" id="gc-id">

<input type="checkbox" id="giftCardSelect" name="giftCardSelect" >
<label for="giftCcardLabel">Use My Gift Card</label>
<div class="hidden-form-gc">
<input type="tel" name="giftCertificate" size="20" value="" onblur="javascript:trimMe(this);checkShowPin(this.value)" onkeyup="javascript:checkShowPin(this.value)" />
<div class="hidden-form-gc-pin">
<label for="giftCardPin">PIN</label>
<input type="text" name="pin" size="3" value="" onblur="javascript:trimMe(this)" id="gcPin" style="">
</div>
<div class="action-item">
<a class="secondary" href="javascript:void(0);" *******="javascript:submitForm2(document.orderReviewForm, 'Apply'); return false;" class="apply">Apply</a>
</div>

Thanks in advance for your help.