In order to impress the interviewer, many graduates wear suits that don't fit well before each interview. In fact, except for industries with strict requirements such as finance, auditing and consulting, most interviews do not need to wear a suit, including the R&D position mentioned by the subject. Too careful dressing will be self-defeating.
Throw away the suit, perhaps the business and leisure style is more suitable for you, and it can give the interviewer a striking image, so that you can meet every challenge with confidence!