If at the review stage I got an audit risk alert to say that my charitable donations exceed 5 percent of my income how is this to be adjusted to not exceed?

No need.

If you've entered your donations accurately and they total more than 5% of your income, it's fine. That warning is just an alert to double-check your figures as it's not common to have donations total more than 5% of your income. If your entries are correct, you can ignore the alert.

Thank you Jennifer .i have been doing my single tax return since I migrated and since I started to tithe to my church so I found it worriesome that 10% of my take home income could show up as 5% in excess of my income per tax slips...you were helpful.