I have set up network od 3 Deco S4 devices. 5GHz network work good enough but 2.4 network has really poor perfomance. While standing in front of main deco router i get 64Mbps which is far away from 30

On app i see star topology with deco router as main point: ISP->deco S4(router)->wireless connection ->deco S4 (fist satelite) //good signal to deco router ->wireless connection -> deco S4(second sate