port forwarding port 53

[FredFresh]

Hi, I tried to port-forward request to 8.8.8.8 and other DNS provider done on port 53 to the iinternal gateways of each sub-lan served by Unbound dns.
(I am talking about devices like vacuum robot where I can't change this setting)

It seems that they "don't like" it: is it possible that even if they are using the port 53, the data they are sending are different from DNS queries?
Thank you