One thing many comments are missing is that you don't have a simple 1:1 relationship with your company and their backlog. You said you have a stand-up, which me

One thing many comments are missing is that you don't have a simple 1:1 relationship with your company and their backlog. You said you have a stand-up, which means you have a team. Work you don't do is work that someone else has to do. If you're literally not working at all some days but claiming you did during standup (as you said in your OP) then the work assignments must be flowing to your team members. In essence, you're asking your peers to pay for your lack of activity with their own work. Nobody expects you to be crunch mode 8 hours per day, but you do need to make an honest effort. Don't be the guy on the team who makes everybody else do most of the work.