Being forced to into a different department and job?
So my situation is that I'm a part time pharmacy clerk. Been like that for a couple months now but recently I guess they changed the way hours are distributed based on the fill count or something like that. Long story short, a lot of hour cuts. To make that happen, my manager is moving someone to do stocking shifts (that way those hours aren't counted as pharmacy) what she originally said only Sundays and asked who would want to volunteer for that position. One of the techs volunteered except one of the sundays she can't come in because it was a requested day off. So, I was chosen to cover for her. Which already I don't want to do because I didn't volunteer for that, I don't want the hours (4 am to 9 am) and it's not the job I signed up for. I want to be in a pharmacy
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But now I got a new schedule and 4 of the days in that week I'm stocking 4 am to 9 am?? Is there anything I can do to fight this? This isn't a role I agreed to nor want. My costco is union if that helps