Date of technical completion not set. Notify your system administrator

What causes this issue?

The <DS:GLOS.system_status>system status</> TECO (technically
completed) is set for the order. The associated date in the order
header, however, was not set due to an error in the program that set
the status TECO.

System Response

The function cannot be executed because the system cannot determine the
period of technical completion.

How to fix this error?

Notify your system administrator or the SAP Hotline.
If necesssary, repeat the calculation of
<DS:GLOS.WIP_calculation>WIP</> or
<DS:GLOS.variance_calculation>variances</> when the date of technical
completion has been corrected in the order header.

Error message extract from SAP system. Copyright SAP SE.