Ios and Android WeChat built-in browsers CSS Position: Absolute; Top:47px can’t realize fixed positioning. I don’t know how to solve it.

  android, question
<body>
 <div>
 <div>
 This layer of div can slide up and down. ios and android WeChat browsers do not realize fixed positioning when the div that should have fixed positioning slides along with this layer of div
 <div style="position:absolute;  top:47px">
 Here is the content of fixed positioning
 </div>
 </div>
 </div>
 </body>

Parent element position:relative, child element position:absolute