src/Taggable.php
protected function removeOneTag(string $tagName): void
    {
        $tag = app(TagService::class)->find($tagName);

        if ($tag) {
            $this->tags()->detach($tag);
        }
    }
protected function removeOneTag(string $tagName): void
    {
        $tag = app(TagService::class)->find($tagName);

        if ($tag) {
            $this->tags()->detach($tag);
        }
    }
Remove one tag from the model

@param string $tagName