Gonna post this to get the obvious stuff out of the way…
First thing you should do is test your Timer. Duplicate it and put it in begin play or something and then put a breakpoint at the start of your RandomRoam function to verify that it’s actually getting called. Or print a message telling you it’s being called.
If it’s not being called, check for typos in both the Timer node and in your function name. Sometimes, I’ve had typos in function names and not realized it. Also try it without a space. Sometimes UE will display a space in function names even though the actual function doesn’t have a space.