Problems accessing customs fields

Hi I'm currently in the process of rewriting some of our workflows for the 2019.3 version of youtrack.

I have several custom some enums , some strings & some dates. It doesn't matter which I try to access I can't get any of them to return a value even though they are all set.

For example I have a field called Request State that can be either Authorized, Acknowledged or Rejected

in the code below I would get two problems depending which is uncommented.

guard: function(ctx) {
 var becomesAuthorisation = ctx.issue.fields.becomes(ctx.issue.fields.RequestState , ctx.RequestState.Authorised); // This returns me an error saying 

// Cannot read property "Authorised" from undefined

var issue = ctx.issue;
var test = issue.RequestState;

var test = issue.field.RequestState;

workflow.message (test);

// The above 4 lines will display a message saying "undefined".  I would expect it to say "Acknowledged".  It doesn't matter however what method I use to read the field set it to the message displayed is the same. I can't see looking at other posts what I have done wrong.  

return becomesAuthorisation ; 
},

I haven't added anything to the requirements section, however based on what I've read I shouldn't need to.  Can someone point me to where I have gone wrong please?