Data to server issue

Hello. So my system uses a RUT956 that reads data from a device using modbus. The issue I have is that if a modbus request fails the router would instead send the next register in it’s place. For example if I have register 1,2,3,4,5 that I want to read and register 3 fails then the router would send register 1,2,4,5 but it would send it as if it was register 1,2,3,4 meaning that the data I received for register 3 and 4 are incorrect. I hope that helps explain my issue. Thanks in advance for any help.