problems with RECORDREF

hi, I need help about using RECORDREF, from couple of hours I get one and the same error , my code is given below it iterates through the fields in the table opened by RecRef):

REPEAT
  IF RecRef.FIELDEXIST(nFields) = TRUE THEN BEGIN
   FldRef := RecRef.FIELDINDEX(nFields) ;
   Type:=  FORMAT(FldRef.TYPE) ;

        IF Type = 'Text' THEN
          Type := 'Text ' + FORMAT(FldRef.LENGTH) ;

        nRow := nRow+1 ;
  END ;
        nFields:= nFields+1 ;
UNTIL nFields > RecRef.FIELDCOUNT;

it works for tables which has Field No. 1,2,3 ...., but if one number is missing and fields are 1,2,6 as in Table No. 9 Customer for example I get error that the field No. 3 do not exist. I tried with:

FldRef := RecRef.FIELD(nFields) ;

but I get the same error.

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