How to use voicemail transcription on iPhone SE 2020 & iOS 13.4

[ForestPhil]

How can I use voicemail transcription (i.e. Voicemail automatically transcribes the text of the message) on iPhone SE 2020 running iOS 13.4?

I have read that O2 supports it and I'm running the latest version of iOS.

I just can't work out how to use it.  There doesn't appear to be an option.

Thanks.

[ForestPhil · Accepted solution]

OK, so Settings > Siri & Search > Language was set (correctly) to English (United Kingdon), and I changed it to English (United States).  This successfully got transcription working, but the transcription itself was terrible.  Probably because I tested it with my (British) voice. Maybe I needed to ask all my callers to put on an American accent when leaving messages ...