Fortinet L2 Support Engineer interview questions

Call from external recruiter, i clearly specified the salary expectations, he said he needed to double check with the hiring manager. Hiring manager gave me a call and I confirmed salary expectations, he was aware and we confirmed to go ahead. Tech interview on site Then after 3 days recruiter gave me a call to offer almost £30000 less than what we confirmed was my salary expectations. I wonder why people want to waste my time? No professional at all.