At a glance

Two lessons for the same group are identical in subject, teacher, and type.

What causes this error

A lesson's signature is a combination of its subject, teacher, and other key attributes within the same group. Two lessons with an identical signature for the same group create an ambiguity the scheduler cannot resolve.

How to fix it

Go to the Lessons section and review the duplicated lessons. If you need two separate lessons of the same subject with the same teacher, check whether they should instead be configured as a single lesson with a higher frequency.

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