Shell expansion within a function

Question

Im attempting to create a function that when called it will create as many files as the value of a parameter given. For instance, if I call it :

ejercicio_VI file 4

It will create file1 and file2 and file3 and so on...

This obviously works manually but it seems it does not work correctly within a function.

Why is my function not expanding the filenames correctly?

ejercicio_VI() {
    if [[ $# -ne 2 ]]
    then
        echo "Esta funcion solo acepta dos parametros"
        return 255;
    fi

    if [[ ! $1 =~ ^[a-zA-Z]+$ ]]
    then
        echo "El primer parametro debe ser una string que matchee con esta expresion regular : ^[a-zA-Z]+$"
        echo "Asi no creamos archivos basura :P "
        return 255;
    fi
    if [[ ! $2 =~ ^[1-9]([1-9])?+$ ]]
    then
        echo "El segundo parametro debe ser un numero"
        return 255;
    fi

    touch "$1"{1.."$2"}


}