Siemens Junior Software Developer (C# .NET) interview questions

Got a call from someone in Siemens and asked me about my expectations clearly mentioned about all my expectations... They went a head with my application.. - 1st round was technical interview, did well and got a call from HR for 2nd round - 2nd round was with the Architect and did really well in that as well.. and got a call for 3rd round - 3rd was managerial round, i was shocked with the question on salary negotiation, because I had clearly mentioned about my expectations before the 1st round itself.. I said it's not negotiable.. still the interview continued... I waited for 3 days for the feedback, i dint get any call so I called back and then the HR told me that my expectation for the salary is higher than their budget.. Seriously at this point you realised about your budget? What the hell were you doing all this while when I was struggling to make sometime for the interview? Seriously i had to struggle a lot and change my plans to attend the interview as I was going to the office and not WFH.. and these people told me at the end after wasting my time that they cannot go ahead because of their budget.. Seriously this is highly unacceptable.. Respect others time as well... Don't just waste others time if you don't have the budget