通过ReplyToActivityAsync发送消息时Bot框架未响应

Question

以下部分通常可以正常工作，但有时无法响应，该消息来自Microsoft Teams。我确定端点已收到消息，但无法将消息发送出去。

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*, 
*::after,
*::before {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    box-sizing: inherit;
}

html {
    font-size: 62.5%;
     /* 80% of view port width which computes to
      font-size of 10.25px for my laptop screen */
}

body {
    font-family: "Lato", sans-serif;
    font-weight: 400;
    font-size: 1.6rem;
    line-height: 1.7;
    color: #777777;
    padding: 3rem;
    box-sizing: border-box;
}

/* HEADER */

.header {
    height: 95vh;
    background-image: 
        linear-gradient(to right bottom,
                      rgba(126,213,111,.8),
                      rgba(40,80,131,.8) ),
        url('../img/hero.jpg'); 
    background-size: cover;
    background-position: top; 

    /*Giving shape to the picture*/
    clip-path: polygon(0 0, 100% 0, 100% 75%, 0 100%);
    /*To make  triangle 50% 0, 100% 100%, 0 100%
    https://bennettfeely.com/clippy/
    */

    position: relative;
}

.header>.logo-box {
    position: absolute;
    top: 4rem;
    left: 4rem;
}

.header>.logo-box>.logo  {
    height: 3.5rem;
}

.header>.text-box {
    position: absolute;
    top:40%;
    left: 50%;
    transform: translate(-50%,-50%);
    text-align: center;
}

.header>.text-box>.header-primary {
    color: white;
    text-transform: uppercase;
}

.header>.text-box>.header-primary>.heading-primary-main {
    display: block;
    font-size: 6rem;
    font-weight: 400;
    letter-spacing: 3.5rem;
    animation-name: moveInleft;
    animation-duration: 1s;
    animation-timing-function: ease-out
}

.header>.text-box>.header-primary>.heading-primary-sub {
    display: block;
    font-size: 2rem;
    font-weight: 400;
    letter-spacing: 1.74rem;
    animation: moveInRight 1s ease-out;
    backface-visibility: hidden
}
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