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Some ideas:
- Did you try re-creating the connection to the TP-Link router?
- Can you ping the txt by its IP address?
- Could you try some other access point?

On the nano Router there is a DHCP server running that is giving the IP addresses to the devices which are setup to use DHCP.
The TXT is asking the nano router for IP address and nano gives it the 192.168.0.11 because 192.168.0.10 is already occupied.
Of course you will see the WLAN symbol in TXT when you got the address 192.168.0.11.
Your network key stored in the TXT is valid and nano offers the next free address to the TXT. Do not change the WLAN setup of TXT.

Check the "DHCP address reservation" option in the nano. Check the MAC address that is reported for your TXT.
Bind the IP 192.168.0.10 to the MAC of your TXT.
Switch off all devices - drop-pod, nano, TXT.
You must find out which device "drop-pod" is! It is connected to your network - if its connection is WLAN based someone had entered the network key, if it is connected to the LAN (cable) interface of the nano you should see the cable .

Start up all devices (except drop-pod) again. Now TXT should have correct IP.

It would be great if you post a screenshot of your infrastructure maybe gathered from "angry ip scanner"
like in viewtopic.php?f=8&t=7877

PLC and RasPi are using fixed IP address setup - you should not change the predefined addresses.
Node-Red app is setup to use the predefined addresses.

Hardware config of TIA portal project is also with fixed IP 192.168.0.1.
So you should keep this!
What was your basic problem with PLC?

Suggestion to have a better control over the IP-addresses in your subnet ('s)
a)
User the DHCP client list to get the mac addresses of all your devices.
b)
Bind all your device to their proper IP-addresses.
After saving the new setting, restart the Tp-link router/switch.
Under WIndows the new binding can also be activated with: ipconfig /renew
To check: ipconfig /all
For help: ipconfig /h
c)
The network address and the reserve IP-addresses depends on the subnet you have chosen by the network mask:
See IPv4 Subnet Calculator: https://www.calculator.net/ip-subnet-calculator.html

One more hint:

Start the beginning of the DHCP - pool from base address 192.168.0.100.
keep the address reservation for TXT on 192.168.0.10.
With that setting you have no overlapping range,
where unknown DHCP devices use addresses of the fixed range (PLC, RasPi,TXT ).