Why does the network disappear when the access point (D-Link DAP-1360) is turned on?

Question

Computer networks

Hello!
Faced the following problem:

• There is a star network of 3 D-Link DGS 1210-52 (no additional settings were made).
  
• There is a router provider TP-Link Archer C20.
  
• There is a domain on Win Server 2019, but not all PCs are in it yet (in the process of connecting).
  
• One of the cabinets has a D-Link DAP-1360 that works as an access point for distributing the Internet via WiFi.
  

All this worked for 2-3 weeks, and at some point when the access point ( D-Link DAP-1360 ) is turned on, the entire network stops pinging each other, while all PCs write that there is an Internet connection.
What could be?
Tried various DNS, DHCP settings.

Answer 1

Figure out what your DHCP is distributing - a provider's router or a domain controller?
An access point to such a network must be connected via LAN, turning off DHCP and DNS in it. It should just work as a bridge, and should not be a router and a DNS server

Answer 2

Maybe your D-Link DAP-1360 is connected via a local port, and not via wan?