verifyElementPropertyValue - casesenstive

I’m trying to write a test case for service api and upon success i need to check whether response contains firstName field value or not irrespective of case (upper case, lower case, mix of it). I’m looking for an option to get value from service and convert it to either lower case or upper case and compare it with data (excel). How do i achieve it?
WS. verifyElementPropertyValue (response, ‘response.details.User.patientProfile.firstName’, firstName)

any idea? this method is case sensitive.

Answered here WS.verifyElementPropertyValue - Casesensitive