Legal advice on salary and scale changes

Questioner

If you started as a teacher with an employer on salary scale 1 and the following school year on salary scale 2, can the employer then transfer you back to salary scale 1 the following year? situation: - first two years contract via P/flex (Randstad), then direct contract with employer. - had good reviews, so no reason for salary reduction. - there was no explicit reference to a salary reduction, I assumed that you would automatically move up in salary scale. If this is not possible, can I still claim the difference in salary afterwards? Or should I have paid more attention before signing the contract?

Lawyer

Lowering salary is not legally the same as paying a lower salary than you received when you were employed through the employment agency. The latter is more expensive for the employer. The lower salary is therefore not obvious. I would ask for an explanation (and guard my own tone).