Myles lodged a claim with the Employment Relations Authority for unjustified dismissal and said the text came as "a shock". There was no previous warning her job might be coming to an end.
She said the position she had held since 2015 was an essential source of income and allowed her to work during the day at a local primary school and care for her grandchildren after school.
She understood another cleaner was hired to replace her soon after the dismissal.
Myles lodged a claim with the ERA for hurt and humiliation as well as unpaid holiday pay and KiwiSaver, petrol allowance and unpaid wages.
The ERA found the dismissal was by text message. There was no evidence to conclude there was any justifiable ground for termination of Myles' employment.
The ERA accepted Myles could not understand why her employment was terminated and never received any explanation.
She understood another cleaner had been employed shortly after to replace her.
The authority found the lack of justifiable reason for Myles to be dismissed caused her humiliation and loss of dignity.
Learning Curves Montessori's managing director, Robyn Toms, informed the ERA she was on holiday in Australia at the time of the hearing and needed more time to respond.
She emailed to say she needed another 14 days to reply but the ERA said no reply was ever received.
Myles was awarded $1365 in lost wages, $7000 in compensation, $1059 in KiwiSaver contributions, $720 petrol allowance, $1125 in costs and $432 in unpaid wages.