If you did not commit the offence as alleged by the University, you should explain so in writing to the University.
If you did commit the offence, then I am afraid the University may take such action as it deems fit. This is what the University's policy is:
"Academic integrity reflects a shared set of principles which include honesty, trust, diligence, fairness and respect and is about maintaining the integrity of a student’s work and their award. Academic integrity is based on the ethos that how you learn is as important as what you learn.
Academic integrity is based upon a number of core principles. For students, this means:
Taking responsibility for their own work and studies;
Respecting the opinions of others, even if they do not agree with them;
Respecting the rights of others to work and study within the ‘learning community’;
Acknowledging the work of others, where it has contributed to their own studies, research or publications;
Ensuring that the individual’s contribution to group work is represented honestly;
Supporting others to behave with academic integrity;
Following the ethical requirements and where appropriate professional standards appropriate to the discipline;
Avoiding actions which would give an unfair advantage over others;
Ensuring that the results of research or experimental data are represented honestly;
Complying with the assessment requirements.
Academic integrity is the guiding principle for all student assessment; from taking exams, making oral presentations, or writing assignments; dissertations or theses for assessment.
Academic misconduct occurs when the principles and values of academic integrity are not adhered to and will often include an attempt by a student to gain an unfair advantage in assessment. Academic misconduct includes: plagiarism; collusion; breach of examination regulations; fabrication of data; impersonation of others, or the commissioning of work for assessment. The University takes any allegation of academic misconduct extremely seriously.
College Academic Integrity Officers
Each College will have its own Academic Integrity Officers who are responsible for dealing with College-level cases (first offences).
Academic misconduct is defined as committing any act whereby a person may attempt to obtain for himself/herself, or for another person, an unpermitted advantage. This applies whether candidates act alone or in conjunction with another/others. An action or actions shall be deemed to fall within this definition whether occurring during, or in relation to, a formal examination, a piece of coursework, or any other form of assessment undertaken in pursuit of an academic or professional qualification at Swansea University.
It is academic misconduct to:
introduce into an examination room any unauthorised form of material such as a book, manuscript, data or loose papers, information obtained via an electronic device or any source of unauthorised information;
present an examination script as one’s own work when the script includes material produced by unauthorised means.
copy from, or communicate with, any other person in the examination room, except as authorised by an invigilator;
communicate electronically with any other person during an examination;
be in possession of any electronic device capable of communicating with other devices or other people during an examination;
impersonate an examination candidate, or allow oneself to be impersonated;
present evidence of special circumstances to examination boards which is false, or falsified, or which in any way misleads or could mislead examination boards;
Examples of academic misconduct in non-examination conditions e.g. coursework, assignments, dissertations etc:
Plagiarism, which is defined as using, without acknowledgment, another person's work and submitting it for assessment as though it were one's own work; for instance, through copying or unacknowledged paraphrasing. This constitutes plagiarism whether it is intentional or unintentional. Each College will advise you about the dangers of plagiarism and ways of avoiding engaging in plagiarism. Essentially, you must reference any material, and acknowledge your sources.
Collusion, which is defined as two or more students or other persons working together without prior authorisation in order to gain unfair advantage and to produce the same or similar piece of work and then attempting to present this work entirely as their own.
Commissioning of work, which is the act of paying for, or arranging for another to produce, a piece of work which is then submitted for assessment as though it were the student’s own work.
Falsification of the results of laboratory, field-work or other forms of data collection and analysis.
The risks associated with cheating are immense, because the penalties that you incur when you get caught could be enough to ruin your career. For instance if you are a Law student you could find that, if found guilty of engaging in academic misconduct, you will not be accepted as a member of the Law Society. Likewise if you are aspiring to become a teacher, doctor or nurse you might find your chosen career path being closed prematurely if you are found guilty of cheating.
The penalties imposed on students vary from warnings, to cancellation of marks for module to being required to withdraw from the University."
The above policy appears here: https://myuni.swansea.ac.uk/academic-life/academic-regulations/taught-guidance/assessment-and-progress-taught/academic-appeals/#academic-integrity=is-expanded
All the best