Device on network:

1. Deco X50 (v1.0) (2 nodes)
2. Deco X20 (v3.0) (1 node)

Firmware installed:

1. Deco X50(US)_V1_1.4.1 Build 20231122
2. Deco X20: US 1.1.5 (rolled back to Deco X20(US)_V3_1.1.4 Build 20230824)

Network Topology:



Issue:
My main node (X50) is placed at the front end ground floor of the house, while the 2nd node (X50) is placed at the first floor living room.
The last node is placed at study room, around 100m away from it with a concrete wall blocking it.

Other devices such as iPhone/Samsung Galaxy Note8/ Xiaomi Redmi Note 11 Pro 5G, has no issues roaming to that node when next to or around the X20 node. But specifically for my  Realme phone is having issues, not able to roam to it when near, where else my Playstation 5, when turn on WiFi, will always connect to it when it is being used at the first floor, which has a wired backhaul X50 next to it with around 20 foot steps away from the X50 node. It is perplexing how would my PS5 will choose to connect to a slower node which is 1 floor below with concrete and tiles separating one floor eventhough the X20 is located in a room right below of that said room where my PS5 is.

If I force it to connect to X20, moving back to where the X50's are , it will not roam back to the nodes. Something tells me that the X20 and X50 are not in good terms or having a bad relationship sort off.

Methods I've tried:

1. Network Optimization
2. Turning off 2.4Ghz
3. Turning Fast Roaming protocol on and off
4. Hard reset all 3 nodes and reconfigure from scratch one by one at a time
5. Setting DNS google on it
6. IoT network is on (I can't turn it off as my Tapo Cams and Bulbs are on it)
7. Not going to move my placement of Deco X20 position as that study room has ethernet cable connecting to it.
8. Replicated the issue by testing it out on firmware Deco x20 1.1.5 still the same, and then rolled back to 1.1.4, still same problem
9. The only way is to quickly turn off WiFi on my realme phone and then turning it back on, only then it will connect to Deco X20, when is next to it, what gives?

Kindly advise, what other methods that I can set the x20 to properly function by handshaking with the other two x50's nodes, this wasn't an issue when I was using a Mercusys Halo H70x previously by placing the 2 nodes at the same spot at Living Room & Study Room. I do not intend to use Connection Preference or Signal Source as that would ultimately defeats the purpose of seamless roaming

Thanks.

EDIT: Turned off fast roaming option, and everything seems to be working as intended, weird.