Scroll iframe on iPhone doesn't work

Question

I know that are many examples showing this problem, but I tried everything and my iframe doesn't scroll on iPhone.

I have this code:

<div id="content">
   <div id="header"><div>
   <div id="container_iframe">
       <iframe id ="external_content_iframe"></iframe>
   </div>
</div>

with CSS

#container_iframe
{
    width: 100%;
    height: 88%;
    z-index: 1001;
    margin: auto;
    left: 0;
    top: 55px;
    right: 0;
    bottom: 0;
    overflow-y:scroll !important;
    -webkit-overflow-scrolling:touch !important;
}

#external_content_iframe
{
    width: 100%;
    height: 100%;
    z-index: 1001;
    margin: auto;
    left: 0;
    right: 0;
    bottom: 0;
    top:15%;
}

Could you help me please?

Answer 1

Please Refer to these Questions, They may have the answer/explanation you're looking for:

Question 1

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