Models cannot be dragged vertically beyond -150° and 150°. This can be increased to -180° and 180° by adding some code to the page.
<script>
Sirv.on('model:ready', (e) => {
const model = e.node.querySelector('model-viewer');
model.setAttribute('min-camera-orbit', 'auto 0deg auto');
model.setAttribute('max-camera-orbit', 'auto 180deg auto');
});
</script>