Ubuntu 18.04 LTS is beyond standard support - Ubuntu Fridge | Extended Security Maintenance for Ubuntu 18.04 LTS began on May 31, 2023
Ubuntu MATE 18.04 being a flavor had an even shorter life - Ubuntu MATE 18.04 LTS reaches end of life
Ubuntu 18.04 LTS is only now supported by Canonical, through ESM. Why ask for support on an unsupported release?
Also note if you re-read your screen; your issue is your choice of an EOL or EOSS release; any supported release of Ubuntu-MATE would NOT have the older packages that create your issue.