Cam my old job me at me for moving on?

So I was at my old job for 4 weeks without any explanation they took me off the schedule for a week, so I started working somewhere else. The old job now put me back on the schedule after 6 days of not having me work and is mad I can't work morning anymore. What should I say to them? I just said I assumed I was fired since you took me off the schedule
Cam my old job me at me for moving on?
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