The University is here to help you through any issues you have with your visa.
I have questions about getting my visa and arranging accommodation before I arrive
There is a lot of pre-arrival information for international students, including about visas and accommodation, on the University's webpages for International Students. This also includes information about when to arrive, what to bring and arrangements for orientation. Make sure to check your letters and other University correspondence for the very latest date the University will accept you arriving and completing your enrolment. If you will not be able to arrive until after that date, do not travel - contact the University to discuss your next steps.
I need advice about my visa
If you are currently on your course in the UK, you can contact the International Experience Team (IET) via Hallam Help, or book an appointment for advice. The IET can advise you about the process for extending your visa, as well as how your visa will be affected if you leave or take a break from your studies, what to do if your visa will expire before you get your results, and what your rights and responsibilities are whilst you are in the UK on a Tier 4 visa, e.g., working in the UK during your studies.
UKCISA (the UK Council for International Student Affairs) has a lot of useful information for international students on its website.