Random devices connected to my gateway

I recently upgraded my router for faster speeds. I kept my password from my old router so all my devices could reconnect faster. All is fine and the same except whenever I connect my iPhone 12 to the gateway. 2 random obscure devices connect as well and they’re named as “OA374D52586B” and “22E282655186” and whenever I go into device details their “model” “brand” and “operating system” all show “N/A

but the weird part is. Whenever I pause these 2 devices. It somehow effects my iPhone 12 wifi. It’s as if I paused my iPhone 12 too. But the iPhone 12 in the devices show that it isn’t paused. Only these 2 random devices. Idk how these 2 random devices are effecting my iPhone 12 wifi connectivity. It’s really annoying and I’m concerned that these two random devices are somehow connected to my home network.

whenever i disconnect my iPhone 12 and reconnect it to the network. Those 2 random devices come back! But with different obscure names again. It’s frustrating. Please someone explain to me what’s happening. Idk what to do anymore.