I have an Ipad pro (12.9 inch, 4th generation), OSx v. 14.2, where I installed LastPass and Google chrome. I went to Settings -> Autofill Passwords, selected Autofill Passwords -> On and Checked only the LastPass app in the list.
However, when I go to a website login page with Chrome, LastPass does not propose me to autofill my credentials: I do not see the usual Last Pass pop-up window, and pop-ups are not blocked in Chrome. Do you know a way around this?
When accessing a site that has a saved login with LastPass, you should see an area above the keyboard that says "Passwords" and you can tap that to view all of the entries in your LastPass Vault which are available for that site. Please also be sure the Google Chrome password autofill is turned off as well by going tapping the three dots icon at the top right of Chrome > Settings > Passwords > Save Passwords should be turned off.
If that doesn't work and you don't see "Passwords" in the bar above the keyboard, could you try uninstalling the LastPass app, restarting your device, then reinstalling and making sure autofill is enabled for LastPass again to test?