Seems a tad too harsh. but well, they do have valid reasons.

You should be more careful in everything you do. Since you are in accountancy field, you must know one of the top qualities companies look for is 'meticulous'. Mistakes like what you had made should not be made twice. If you are not a meticulous person by nature, train to be one. If you find it too difficult, perhaps you can go for jobs in finance instead of accts. Go think about what you really want or interested in.

Repetitive mistakes wont reflect good on you and will only make pple think u v bo chap and lazy. Perhaps you should have put in more effort?

Anyway, first job for most pple is adjustment period and tough to get by. Dont give up if it's really what you want!