Cause

The cross-section of the routed connection is larger than the cross-section set in the connection point pattern of the part placement in the Max. wire cross-section column.

Solution

1. Reduce the value of the cross-section at the routing connection (or the corresponding multi-line connection in the schematic) so that it amounts to no more than the value entered in the connection point pattern in the Max. wire cross-section column. Or, alternatively, adjust in this column the cross-section value to the cross-section of the routing connection by increasing the value accordingly.
2. Then start a new check run.