Can a person reopen a settlement if they were not mentally stable during the process?

Mental capacity is a valid claim to undo a settlement. See for example an unreported NJ Appellate Division case of Ressler v. Small 2007 WL...

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2009 Income Tax preparation problem

The return preparer firm and individual should be responsible to pay the penalties and possibly interest. See the case of Ronson v. Talesnick...