If the job responsibilities and duties shared during the interview differ significantly from what you end up doing on the job, it is absolutely reasonable to reconsider your position and possibly resign. It is important to have clear communication with your employer about job expectations and responsibilities before accepting the offer or starting work. Regarding the contract, it would be best to review any terms or clauses that mention resigning or termination before making any decisions. However, if the job is causing you excessive stress and anxiety, it may be best to prioritize your mental health and well-being and evaluate whether staying in the job is worth it. Ultimately, the decision to continue working or resign depends on individual circumstances and personal priorities. It is recommended to speak with HR or a supervisor about any concerns or issues before making a final decision.