Writer keeps reverting to British English

Hi, I’ve really had it with Writer. On some days this problem never seems to happen. Basically, while writing, I notice the red little line under words like “behavior” and I realize it’s set to British spelling so what I do is select all, then tools/language/all text/English (USA), and save and it seems fine. But sometimes, like it’s been happening recently, I am working on a document and do this thing, and the red line goes away but a minute later it’s back, like it doesn’t stick. What am I doing wrong?

What is your default locale set to? Tools → Options → Language Settings → Languages. There might be some conflict.

ve3oat, thanks for your reply.
This is what I have.

Language of:

User interface: Default English USA

Locale setting: English USA

Decimal…: Same as locale setting (checkmark)

etc.

In the Default Languages for documents,

Western: Default-English USA

Asian (not checked): Default Chinese (simplified)

Complex test layout (checked) Default Hindi

Not sure why it has Hindi and Chinese, I speak/write neither, but anyhow, this is what I have.

The cause of your problem is not known to me. Sorry. Hopefully, maybe someone else can suggest a solution.

Thank you for your help anyways, appreciate it.

And what is the input language?