Phpbb3 Language issue

We installed the phpbb3 app on our DH account, however the only language option is “British English”. While this is not an issue with reading the forum, it is a big issue with our sight impaired members using Dragon or other text to speech converters as the converters add a British accent.
Anyone else have this issue or ides on how to get the American English option added so I can select it ?
I have not been able to find this on this forum yet, if I missed it please forgive re-posting.

You probably just need to install more language packs - or the one you need.
See this: