I’ve split my WiFi channels but still can’t select 2.4ghz. Any advice??

Hi. First time poster! I have 5ghz WiFi but split it to allow me to access 2.4ghz. I’ve named them separately and they appear as such on all other devices but when going through the set up process for my Ring doorbell 2 I can only see one WiFi choice and not the 2.4ghz or 5ghz options. When I get to the point of connecting to wifi in the set up it simply times out and stalls. I’ve numerous times in different spots around the house with no luck. Any advice welcome as I’m going to be returning the product if this doesn’t work! Thanks.