I’m not saying that the GL.iNet products are perfect. They are not. But you have to understand that the use of a repeater (or another router) within a network is not normally wanted by the network owner.
If this is a farm somewhere in the furthest corner of Scotland - then the fault presumably (!) lies elsewhere. But with large hotel chains or professional companies, it will always be more difficult.
I have fewer problems with my Opal than with the Flint - but in the end it always depends on the situation and your own knowledge.