ESP8266 WIFI Problem

I have a mini nodemcu project to measure temperature, the ESP8266 is powered by battery.
It works fine when in range of the modem.
I also have a range extender (TP-LINK TL-WPA4220) which is working fine but the project fails to connect to it.
I notice that the TL-WPA4220 is using WPA/WPA2-Personal protocols while the house modem is using WPS PSK. Perhaps this is the problem.
Any help would be appreciated.

Simplify. Use some other device like a phone to get connected through the extender to the base modem. Then try your esp8266, it should now work.

Thanks, have connected with mobile 'phone. It shows:-
TP-LINK_5C90
72 Mbps
WPA/WPA2-Personal
192.168.0.100
Not sure if that's what you meant but it didn't make any difference.
P.S. When doing the same with the base modem I get:-
Vodafonexxx
72 Mbps
WPA2 PSK
192.168.1.7

Different networks or sub-net? 192.168.0 vs 192.168.1 Change the extender to use 192.168.1

Apologies, haven't had time till now.
I can change the IP address of the remote WPA4220 using my android 'phone.

Looking at the base modem I see IP is set to DHCP and IP address is xxx.xxx.1.1 or xxx.xxx.1.103
Changing the remote WPA4220 to these addresses didn't work.
I'm stuck now.

I am not sure what you are talking about. Disconnect the range extender. Does the app work with the base now?

I will assume the previous step worked, now connect the extender using one of the following procedures (it looks like you will have to use #2 as you don't have a WPS button on both routers) In order to get the links to work, here is the google search string [howto add an extender to my router]

Sorry, that was done in a hurry.
The base modem show an IP of xxx.xxx.1.1 when checked with an Android 'phone (/connections) and xxx.xxx.1.103 with the Fing app.
Yes the project works fine with the base modem

Another sorry! our messages crossed.
The extender seems to be working OK, I can connect to it near its location using my Android 'phone, the 'phone also shows that it is beyond the range of the base modem.