"It's been an amazing opportunity and learning experience being a part of @360hit - time to move on to other things!" Tracey captioned her post.
The letter revealed that the resignation is effective immediately, and was also signed by the company's director - and Tracye's current boyfriend - Nathan Constable.
The letter read: '"We confirm Tracey is not a director, shareholder or employee of our company but a much appreciated Ambassador of our brand."
Back in June the troubled reality TV star was hit with a court order requiring her to pay her ex-boyfriend Patrick Kedemos over $20,000.
The order, from Perth Magistrates Court, comes after Tracey failed to repay a "business loan" given to her by Mr Kedemos in 2018, News.com.au reports.
The MAFS bride was also hit with an additional charge of six percent interest plus legal fees on top of the $20,000 lump sum.
Mr Kedemos, an investment banker, described the judgement as "a moral victory", Perth Now reports.
Tracey was in a relationship with Mr Kedemos until July 2018 when their romance ended during a highly publicised holiday to Berlin.