I need smb to finish the implementation of an API on my website

hi.
i need smb to finish the implementation of an API on my website. the person who worked on this could not manage to finish it. about the payment step the guy said „we use sandbox API and need to move to Prod API to check payment.”
What I can deliver is the offer listing page. Need to use real API to process payment
it would be better to be smb who can speak Romanian because the website is in Romanian and there are many details in Romanian.
the page helps drivers to get quotes from different insurance companies.

here it is the page where you can see what was done regarding the API implementation https://vreau-asigurare.ro/asigurare-rca/
i tested with real data and i can not go to the next step and there is no error message to say what is wrong.

here it is a similar page from an insurer which uses the same platform https://euteasigur.ro/insurance/rca/form

more details will be provided at the right time.