I have purchased a TP-Link Deco M5 3 unit mesh. I am working through the setup using the APP to setup first unit. I have reached the section on connection type. I have chosen PPPoE and have typed the username and password provided by Vodafone. I have then turned on IPTV/VLAN settings (not sure if I needed to) and chosen custom mode and added internet VLAN ID of 101 as advised by Vodafone and chosen 1 at random for VLAN Priority.802.1Q tag is ticked by default and there is a section on IPTV VLAN to fill in. Is this actually required? Regardless of filling in or not everything seems to progress. I enter a wifi name and password to create a new wifi connection. I am prompted to connect to my created wifi. Immediately the deco unit LED goes red and when testing the internet connection on the APP it states unable to connect to the internet. I have tried everything including unplugging the router. What am I doing wrong. This is doing my head in now for a product that is plug and play. I am not a techi!