Great catch! I've figured out the problem. My API actually returns[0] the IPA for both UK and US accents. The problem was it was under the tags "Received-Pronunciation" and "General-American" instead of the usual "En-uk" and "En-us".

I will deploy a fix soon. Thank you!

[0]: https://dict.apihost.site/v1/define/en/dog

EDIT: I've deployed a fix. This still won't cover all the edge-cases but it's much better than before.