Airscan quality poor

Details please......any details.....???

Happens when I try scanning with Xsane or Document Scanner.
The scanner is a Lexmark MC3326
The scanned documents are of very low resolution and when I change the resolution in Document Scanner nothing happens.
Using Ubuntu 21.10

https://support.lexmark.com/en_us/drivers-downloads.html?q=Lexmark%20MC3326
Driver files for 64-bit Linux distributions with Debian-based packaging

Bernard thank you for your suggestion.
 I used to use the Lexmark drivers which supported scanning with Xsane for USB connected devices.
Having updated my firmware and reinstalled the drivers I have the following array of printers and error messages:
Document scanner
a) Lexmark MC3326adwe, the Lexmark scan driver starts but I am unable to load a profile and start the scan
b) Lexmark Network, I get the error message Invalid IP/hostname you have specified is invalid. Please provide a valid IP/hostname
c) eSCL Lexmark MC3326 scans but poor quality as before
Xsane
a) Lexmark Network Scanner [Lexmark_nscan:libnet/SPECIFY DEVICE]
b) Lexmark MC3326 the Lexmark scan driver starts but I am unable to load a profile and start the scan
c) eSCL Lexmark MC3326ad ip= 192.168.1.72 scans but the quality is poor.

Can you suggest a valid ip/host name or how do I specify device?

The IP/hostname is the one it gets on the network. Changing this doesn't change quality and we have no way of knowing this information. It will change network to network so only you will know the IP/hostname of the device

There is a difference between the Lexmark MC3326 and MC3326adwe drivers are different drivers.

https://www.lexmark.com/en_us/printer/14450/Lexmark-MC3326adwe
Install: Network and Local scan driver for 64-bit Linux distributions with Debian-based packaging
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Install: Driver files for 64-bit Linux distributions with Debian-based packaging
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Driver files for CUPS-based systems