Attribute change in RCOIS API

Hi,
Customer is having following product structure

Root Product
                    > Relationship R1
                            > Product A or Product B
                    > Relationship R2
                            > Product C
                                    > Attribute Value 1 or 2
                    > Rule 1
                            > Product A from R1 requires Attribute = 1 of Product C from R2
                            > Product B from R1 requires Attribute = 2 of Product C from R2

If we are placing any order we are getting product structure as

1) Root Product >
                R1> Product A
                R2 > Product C with Attribute = 1

Or

2) Root Product >
                R1> Product B
                R2 > Product C with Attribute = 2

When we are changing Product A to Product B by clicking Customize button in eConfigurator it gives conflict message as the attribute value is still 1 for product C.