As discussed, we have already checked Tata equipments over this circuit and there is no change in configuration that would cause bandwidth limitation. They are same as they were at the time of service delivery.
However, your end client has changed the router at Paris and as you confirmed this issue started since then. I would suggest you to check with end customer if the configuration of new router is same as older one.
This new router may be limiting the traffic flow. I’ll await your revert on this.