Hello mam
As per your problem posted here it is very difficult to answer until unless it is accompanied by any photographs and radiographs. Best way to correct a cross bite is through orthodontic treatment so visit your orthodontist for the problem.
Next Steps
visit your nearby orthodontist
Health Tips
even if orthodontic treatments takes time it's still best way to get the cross bite corrected. rest up to you and your dentist to decide.
Regards