YES! KUBOTA told me that yesterday! They Stink!
I had a similar experience with Frigidaire of Canada.
They would not talk to me unless I had a tech code.
In very rural Canada I got lucky, and found an old tech who was well past his prime .....nice old guy.
I paid him to stand by, and with me using his code, I trouble shot the unit, making believe all the while that I was him.
I think most companies do not provide homeowner tech support.