Why does flex block ride on IE11?

Question

css

Comrades, in general, I just can’t fix the button that has gone on ie11, it needs to be in the center, what could be the problem?

<section class="request">
        <div class="container">
            <div class="row">
                <div class="col-md-12 request-btn">
                    <a id="go" href="#" class="com-btn">Отправить заявку</a>
                </div>
            </div>
        </div>
    </section>

.request {
  height: 200px;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-pack: center;
  -ms-flex-pack: center;
  justify-content: center;
  -webkit-box-align: center;
  -ms-flex-align: center;
  align-items: center;
}

.request-btn {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-pack: center;
  -ms-flex-pack: center;
  justify-content: center;
  -webkit-box-align: center;
  -ms-flex-align: center;
  align-items: center;
}

.com-btn {
  width: 360px;
  height: 80px;
  border-radius: 6px;
  background: #ff9927;
  -webkit-transition: 0.2s;
  -o-transition: 0.2s;
  transition: 0.2s;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-pack: center;
  -ms-flex-pack: center;
  justify-content: center;
  -webkit-box-align: center;
  -ms-flex-align: center;
  align-items: center;
  text-align: center;
  color: #ffffff;
  font-family: "Raleway";
  font-size: 22px;
  font-weight: 400;
  line-height: 26px;
}

Answer 1

And what do you want to do then? Is it centered or what? )