All tags must have enclosing tags. In my case, the hr and input elements weren't closed properly.
Parent Error was: JSX element 'div' has no corresponding closing tag, due to code below:
<hr class="my-4">
<input
type="password"
id="inputPassword"
class="form-control"
placeholder="Password"
required
>
Fix:
<hr class="my-4"/>
<input
type="password"
id="inputPassword"
class="form-control"
placeholder="Password"
required
/>
The parent elements will show errors due to child element errors. Therefore, start investigating from most inner elements up to the parent ones.