Anemone move all the time. Generally when not happy with current spot. Whether lighting, flow or parameters. Sometimes they just feel like taking a walk.
Welcome to R2R by the way. A little more information about your tank could weed out any problems. Like what type of lighting? List your parameters and tank age also.
It's very normal for new anemones to move around after introduction. Long tentacle anemones need to bury their feet in the sand several inches deep to feel safe, they may wander for a little longer if there aren't any areas of suitable depth.
Welcome to the hobby by the way! You chose a great nem to start with.
Anemones are photosynthetic and respond to both light and water movement. They will and do favor a certain environment until they find their happy spot. Monitor water conditions regularly to avoid any major changes. Ammonia and nitrate levels should be undetectable at all times using a good quality test kit and Not API either.
Here are some water parameters to follow.
Water temperature: Between 77°F and 82°F (stay close to the middle of this range)