Why is Bootstrap Vue's Tooltip Disappearing Quickly?

Question

Bootstrap

Hello! Using bootstrap Vue, the problem is that when you hover over a button that uses a tooltip, the tooltip appears and immediately disappears. Why is this happening I don't understand

<b-button
       v-if="showBtn"
       v-b-tooltip.hover.bottom="$t('table.showDetails')"
      @click.stop="showUserInfo"
     class="mr-2 btn-icon btn-icon-only btn-sm"
     variant="info"
>
     <i class="pe-7s-look btn-icon-wrapper" />
</b-button>

process video at the link:
https://youtu.be/df4JT-ry-gg