Interview is the main part if you want to get hired in the company on the vacant position. In case hiring manager asks you any question and you give the answer like that “I put that on my resume” is totally wrong, off course you put on the resume but you should need to tell him again.
Candidates can also will lose their job if they will do the badmouthing your ex-boss. What you need to do is talk about educational qualification, experience, etc not regarding the ex boss and all west topics. In case hiring manager asks you then give the polite answer and say something interesting.
Answering your cell phone mid-interview is the biggest mistake in the interview. If you are answering the cell phone in the interview then it means that you are not interested in the job interview. Interview is all about the physically and mentally present of candidates. You must switch off your cell phone while interview is running. The hiring manager realizes that you need this job which you are interviewing for.
Dress up unsuitably is also the biggest mistake because you are going to save your future through your job. Job interview is your chance to secure your future and you always need t5o dress up properly while going to face the job interview.