Original poster back to tell you what happened.
We were hand baggage only. Allowance was 7kg.
We had two cabin bags, with a combined weight of 13 kg per person. But it was not possible to upgrade cabin bag allowance on this route..l to 14kg which was the original plan.
So we decided to pay for one checked bag each.
Used mobile check in but it didn't issue boarding passes because it was necessary to go to the check in desk for documentation check.
Handed over the trolley bags that would normally go in the cabin with us.
That left us with a back pack each which was not weighed at the check in desk or at the gate.