WIreless connection starts and then drops

[FatalErrorMan]

After switching on my printer picks up the wireless network. I can make one scan but if I then try another or to add a page this operation fails and then the printer gives its status as offline. 

I have done all the rebooting of my router and printer. I have run scan doctor. 

A wireless network test report states that more than one access point can be seen by the printer with the same SSID. This is because I have an extender that mimics my router. This is standard so I don't see how I can resolve this as reducing signal power or turning off the extender is not an acceptable solution

[8lives]

Check the firmware, latest is 2023A.

[FatalErrorMan]

Thanks for your response, so quickly.

Status report says: NLM5CN2023AR so I guess that's 2023A.

I found something online that advised to turn off IPv6, which I have done. This allowed me to scan 4 or 5 pages into one file but then the same issue returned for adding one more i.e. would not scan and then printer registered as offline. I can usually get it back online with a power cycle but the issue remains in that in can't usually scan more than a few times before going offline. 

[8lives]

If your router is running both the 2.4 GHz & the 5 GHz bands make sure to assign separate SS|D's.

[FatalErrorMan]

Yes, I have done that. The 5GHz is differs by having "-5" at the end of the same name.

I am not a novice but neither am I an expert. It is very frustrating that this product, that was doing fine before, is struggling as it is.

[8lives]

Does the problem happen when the extender s turned off?