How do I reverse virgin router optimisation setting

[HTrav]

Virgin kindly suggested the setup I had with two ranges 2.4 and 5 wasn’t the best, changed it to one range, now I have no ability to use different ranges in different rooms based on need and the Wi-Fi strength has gone from 110 to 5 … and others rooms no Wi-Fi signal at all,

please help out me out of my misery 

[Client62]

In the Hub's menu  : Advanced Settings >>> Wireless signal > Disable Channel Optimisation  ( this will unlock the ability to change the SSIDs for each band )