Why do I get the following error when I am adding schema to my Form: Uncaught (in promise) TypeError: branch is not a function

Question

I am getting the following error when I am adding schema to my form, error:

Uncaught (in promise) TypeError: branch is not a function

Following is the yup based schema that I am adding to my form:

export const mySchema = (t) =>
  yup.object().shape({
    type: yup.string().required("Type is Required"),
    gType: yup.string().when("type", {
      is: (type) => type === "TYPE1" || type === "TYPE2",
      then: (schema) => schema.required("G Type is required"),
    }),
    identifier: yup.string().when("type", {
      is: (type) => {
        return (type === "TYPE1" || type === "TYPE2");
      },
      then: (schema) =>
        schema.required("Identifier is required").matches(/^.{13}$/, "Identifier Must be Numeric"),
    }),
    extension: yup.string().when(["type", "gType"], {
      is: (type, gType) => {
        return (type === "TYPE2" || gType === "IDTYPE");
      },
      then: yup.string().required("Extension is required"),
    }),
  });

The issue is mainly happenning for the extension field where I want to make the field required based on 2 diffrerent field values type and gType. But when I check for the values I am able to console.log them within the yup schema:

is: (type, gType) => {
        console.log("Type : " + type)
        console.log("GType : " + gType)
        return (type === "TYPE2" || gType === "IDTYPE");
      },

But for some reason I am getting the above mentioned error along with the console.log. I have checked my vee-validate Form and Field and provided the name and everything. If I remove the extension from above schema then everything works fine but adding it fails.

I also tried to obtain the array something like this, but doing so I am able to get only the type and gType for some reason shows as undefined:

 extension: yup.string().when(["type", "gType"], {
      is: (values) => values[0] === "TYPE2" || values[1] === "IDTYPE",
      then: yup.string().required("Extension is required"),
    }),

Can someone please let me know how to fix this issue?