Hi Lewis, welcome to the forum!
How many LEDs are you trying to drive? They can get quite power-hungry, and some types of strip will not light at all if they aren’t getting the current they’re after.
If you could also make up a small schematic of how you’ve got everything connected, that’d be most helpful (hookup wires like these can be a little hard to follow, especially with a LLC we don’t have experience with. Sometimes even just drawing up the schematic of how things are supposed to be connected points out
Keen to get you back on track!
-James
