you need to explain clearly which modules/exams you are asking for the ECs for, its its just one fine - but explain that it is only the exam (not coursework aswell) for module XXX. Then explain why you need ECs taken into account, not just moaning, state what was wrong. If you can get/have got a doctors note for it put that it. Then just finish saying that for the reasons you have stated above you are asking for your ECs to be taken into account with regards to the mark you have acheived in this examination