The CRS provides two endpoints: one for checking that the protocol was executed properly, and other one to initiate a dispute when a Consumer claims that he cannot decrypt the cipherblock he has been invoiced for.
The endpoints require JWT bearer authentication. The JWT can be obtained after performing a login with OIDC and presenting valid i3-MARKET credentials.

A complementary Conflict-Resolver Service (CRS) has been developed, which can be run by any trusted third party to issue verifiable signed resolutions regarding the execution of the NRP.
The Conflict-Resolver Service (CRS) can be queried to provide a signed resolution about the non-repudiation protocol associated to an invoice being valid or invalid. It could be invoked by either the consumer or the provider. The latter should be mandatory, being the resolution sent along with the invoice to the consumer.
However, this resolution does not ensure that the published secret could be used to decrypt the encrypted block of data. If the consumer B is not able to decrypt the cipherblock, he could initiate a dispute on the CRS. The CRS will also provide signed resolution of whether B is right or not.