Ionic app of Android and iOS need to be stable for us -- 2

We have Ionic based apps, developed and deployed in Android and iOS.Our team is not expert sowe are lagging with basic functionality,like OTP,signup,Orders,Payments etc.So we need someone, who can help our team to fix UI,API and other existing issues and development, so that a basic flow can work.Our team will work,with Freelancers, and they will take mantainance and for new functionalities we will get your help
We need to make UI/UX more attractive and all functionalities should work