If a newly purchased plant wilts it could be several different reasons.
The change in environment can stress plants. Proper watering and light conditions are important.
If the plant is dry you can place the pot in a sink or bowl of water and allow the plant to drink the water for 15 to 20 mins. Then let the plant sit to drain any excess water.
If the plant was overwatered, allow it to dry out. This can be more difficult to overcome as root rot sets in quickly.
Here is a link to refresh you on the care requirements.