Avo caf is a boutique eatery in the inner-west of Sydney. Claire is the owner and manager of the business and runs the business on a day to day basis with her 4 casual staff employees. The shop is located in a busy shopping centre called Hallelujah Plaza. Claire signed a retail lease agreement with the lessor, Orion Pty Ltd for a five year term from September 2019 at $1000 per week. With a 50 person capacity and a full contemporary Australian breakfast and lunch menu, the caf has been hugely successful and nominated as the finalist in the Inner-West Local Business Awards in the last few years. However, the high turnover of the business has started to drop with the outbreak of COVID-19 pandemic and it has reduced to a significant level. Claire has informed Orion about her difficulty to continue with the lease at the agreed amount of the rent and requested to reduce the rent. On her request, Orion has agreed to reduce the rent to $600 per week from September 2020 onwards until the situation improves. Meanwhile, Claire has diversified her business with an online delivery option which has become profitable. Consequently, Orion has sent Claire a notice to pay the regular weekly $1000 rent from September 2021 to the end of the lease agreement. Orion has demanded that Claire must also need to pay for the $400 difference between the actual rent and the reduced rent which has been exempted for an entire year.

question : Advise Claire what relevant legal arguments she can bring against Orion Pty Ltd for their claims using contract law principles. In Austtralia Law