[osmo-sim-auth] Only AUTS returning

Hello everyone, a student college and me are using the osmo-sim-auth tool for a student project. We have valid data for our SIM card since it's a special ordered test SIM card. In 2G mode we get the correct RES value, but in 3G mode we always get only an AUTS value. We calculated the SQN value from the AUTS to verify that we have the correct SQN value, but still we only get AUTS as return. I would be grateful to hear if any of you have an idea why this is happening. Best regards Marco