Problem with Extra Material in Scriputre Reference Settings

Apologies, this turned out indded to be a keyboarding problem. Resolved

A team I'm helping has set up their Scripture refs. and in the Extra material have Tichák'imɔ́ ko (meaning see). This has been copied from the text typed in PT to ensure there are no issues with misspellings or using the wrong keyboard. However when I run basic checks the Extra material is shown as an error every time. What is wrong with the set up?