HP Office Jet Pro 9010 stopped being able to print double sided

I have been using Ubuntu Mate for about 4 years now, exclusively. It is the only operating system on this computer. Started with 16.04 and iterated up to now 19.04 and have been very happy.
I recently purchased a new printer because the old one died of old age. It installed on Mate with no issues. It was downright easy, and all print features worked like a charm, even the duplex printing.
Now, about a month later, after "losing" the printer because I changed ISP's and had to connect to a new router, the printer is working fine, except the double sided printing is now listed in the properties as "unavailable" and is greyed out.
Can anyone help with this? I have been trying not to resort to third party or proprietary drivers. I currently have not used any in the last four years and do not want to start now if I can avoid it.

Hi

internet reading suggests 2 likely causes

a) You have selected a driver which is not duplex so 2 sided is not an option available

b) When you open a doc to print, you have not found the setting to use duplux and simply pressed print

Hps can be set up using cups or using hp-setup

which one did you choose?

also did you see one or more models that matched your printer when you set it up?

I don't have hplip installed but cups has a only one driver which matches your model
maybe you need to install hplip-gui?