Error TRQ0020 when save a transaction

Dear experts,

When I try to save a transaction, I got an error mesage:

No position exists for the selected criteria

Message no. TRQ0020

Diagnosis

This is the position that is characterized by the following details:

CC=1000;DN=\INTERN\0005;PT=51Z

Explanation of the abbreviations used:

PT Product type

CC Company code

DN Transaction number

We activated business functions FIN_TRM_LR_FI_AN and FIN_TRM_LR_FI_AN_2, and then ran all the settings for migration in TPM_MIGRATION. As we had a new system almost without any data, we did migration without any troubles.

Could you, please, tell me, how to correct this error? What can be it's reason?

Thanks in advance

Irina