Oh that is really rubbish and I feel for you particularly if you are currently in audit and therefore in busy season.
There tends to be a phone call prior to the decision of you being fired and they look at exam failures as a whole, eg bad fails/second time fails and they say how will we treat them, sometimes if attrition is high they will allow bad fails for instance.
The appeal process is pretty tough to overturn as they don’t love information presented post the decision, feel that extenduating circumstances should have been agreed pre taking exam. This all being said I have seen appeals be successful. They will often consider how far through your exams you are, eg if you failed a first one there considering if you will be successful for the rest.
At my firm we often take good candidates from audit and place them in advisory but again often depends how far through you are.
Dependent on how far through you are you do need to consider if you really want this, eg if it’s one of your first exams then do you want to spend the next few years taking exams? Maybe there is another career you would prefer?
Also, whilst your contract probably says one month very often during busy season they will extend the notice period to 3 plus months as they need you.
Do you have a coach/people manager you can talk this through with? Are you close to Any partners? You’ll be amazed at individual partners influence in this.
Wishing you well