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

We have one running apps, developed using Ionic framework, which are deployed in Android and IOs.However,our team is not expert and due to that,app is failing in basic functionalities, like OTP logins,Orders,Payments etc.We need someone, who can wook with our team, and help them to create a simple flow,signup,login,OTPs etc..We will take over the work,and we will be keep connected with the Freelancers, who will help us,to add more features, and maintenance will be done by our team