(Lots of pictures) Network bridge and 2 Mikrotik router. Not all packets get through. Why?

Question

Computer networks

Situation. There is a MikroTik RB751G-2HnD (RouterOS 6.29.1). It has its own network on each (except ether1) physical port:

• ether2 - 192.168.2.0/24
  
• ether3 - 192.168.3.0/24
  
• ether4 - 192.168.4.0/24
  
• ether5 - 192.168.5.0/24
  

Accordingly, in each of these networks, it is the default gateway and DHCP server with addresses:

• 192.168.2.1
  
• 192.168.3.1
  
• 192.168.4.1
  
• 192.168.5.1
  

ether1 - Internet source.
There was a need to add equipment physically remote from the RB751G-2HnD to the 192.168.3.0/24 network. It was decided to do this through a Wi-Fi bridge. This is my first practical experience with bridge. The scheme turned out like this:

I.e. made Virtual AP on RB751G-2HnD (named gostinnaya). Next, on the RB751G-2HnD, I made a network bridge consisting of interfaces:

• ether3
  
• gostinnaya
  

I purchased MikroTik hap Lite (RouterOS 6.29.1), connected equipment to it (actually, it's a test computer for now). And MikroTik hap Lite connected via wlan1 (station mode) to the Virtual AP created on the RB751G-2HnD. At the same time, on MikroTik hap Lite, wlan1 was added to the default bridge-local (which was created by pressing reset on the device to reset it to default settings) and removed the DHCP server.
As a result, MikroTik hap Lite received the DHCP address 192.168.3.204, and the test computer connected to it 192.168.3.203. At first glance, everything works as it should. But there were problems during the verification. It turns out that not all traffic between Mikrotiks passes. It appears like this.
ARP-ping from hap Lite to RB751G-2HnD does not go through the bridge:

The same, but through wlan1 - does not go:

ARP-ping in the opposite direction (from RB751G-2HnD to hap Lite) goes:

but ping from RB751G-2HnD to hap Lite does NOT go:

ARP response to an ARP request from 192.168.3.201 (NAS) to 192.168.3.204 (hap Lite ) is returned. In the opposite direction (from hap Lite to NAS) - no. Before each test, the ARP table of both devices was reset.
Ping 8.8.8.8 from hap Lite (192.168.3.204) does not work, trace to 8.8.8.8 shows:

At the same time, on the RB751G-2HnD, pings from hap Lite to 8.8.8.8 can be seen in both directions.
There (from hap Lite to 8.8.8.8):

Back (from 8.8.8.8 to hap Lite):

However, the answers from 8.8.8.8 did not reach hap Lite.
The same situation is with the test PC (192.168.3.203), which is connected to hap Lite.
But if the PC (192.168.3.203) is connected from hap Lite to ether3 to RB751G-2HnD (through an unmanaged switch), then the PC receives the same address 192.168.3.203 via DHCP. But the Internet (in particular, pings up to 8.8.8.8) appears on it:

Network bridge settings on hap Lite:

I did not add anything in the Filters and NAT tabs.
Routing table on hap Lite:

192.168.88.1 remained after the default settings, it seems that disabling this (disable in IP->Address) did not change the situation.
On both Mikrotiks there are no rules (in IP->Filters) preventing INPUT\OUTPUT\FORWARDING traffic to each other.
On both Mikrotiks there are no rules in Bridge->Filters and Bridge->NAT.

Answer 1

The issue was resolved. Now I'm not near the equipment. Maybe I'll post some pictures when I do. But the bottom line is this. On hAP Lite, in the Webfig control panel on the Quick Set page, I saw a checkbox named "Bridge all LAN". There was no check mark. I thought - how is it so, if I manually stuffed all the ports into the bridge? It turned out that not all.
As I wrote:
Those. ether1 was not in my bridge.
ether1 was specified in the DHCP client. Here (in the DHCP client) wlan1 was specified, to which 192.168.3.204 was issued.
Final decision:
1. add ether1 to the bridge. I did this in the Webfig control panel on the Quick Set page, ticked the "Bridge all LAN" box. Although this is not the only way
2. In the DHCP client, deactivated the entry about ether1
3. In the DHCP client, wlan1 replaced with bridge_local

Answer 2

Is the firmware version up to date?

Answer 3

Did you mess with the gateways? Try putting the bridge in a separate /31 subgrid and setting up routes. Do not bridge interfaces.

Answer 4

an interesting bike)
and in hAP in IP-DNS-Static - is there a thread?