word-wrap not working in flex-item inside row flex container

Question

Why is word-wrap not working in a flex-item inside row flex container?

CSS

.container {
  width: 300px;
  border: 2px solid red;
  margin: 0 0 20px 0;
}

.text-container {
  background-color: cyan;
  word-wrap: break-word;
}

.flex-row {
  display: flex;
  flex-flow: row wrap;
}

.flex-column {
  display: flex;
  flex-flow: column nowrap;
}

HTML:

<div class="container">
     <div class="flex-row">
           <div class="text-container">
              ThisIsAVeryVeryLongWordWithNoSpacesInBetweenDoesNotWrap
           </div>
     </div>
 </div>

 <div class="container">
     <div class="flex-column">
         <div class="text-container">
             ThisIsAVeryVeryLongWordWithNoSpacesInBetweenWraps
         </div>
     </div>
 </div>

.container {
  width: 300px;
  border: 2px solid red;
  margin: 0 0 20px 0;
}
  
.text-container {
  background-color: cyan;
  word-wrap: break-word;
}
  
.flex-row {
  display: flex;
  flex-flow: row wrap;
}
  
.flex-column {
  display: flex;
  flex-flow: column nowrap;
}

<div class="container">
     <div class="flex-row">
           <div class="text-container">
              ThisIsAVeryVeryLongWordWithNoSpacesInBetweenDoesNotWrap
           </div>
     </div>
 </div>

 <div class="container">
     <div class="flex-column">
         <div class="text-container">
             ThisIsAVeryVeryLongWordWithNoSpacesInBetweenWraps
         </div>
     </div>
 </div>