Revolut to Google Sheet Integration

I need to connect my Revolut Business account to an existing Google Sheet via Google Apps Script. The integration should pull transaction history and account balances on a scheduled basis (e.g., every 15 minutes / hourly — it does not need to be real-time) and write the data into the existing sheet structure without breaking current formulas or reporting.

Requirements

Implement using Google Apps Script (bound to the existing Google Sheet)
Integrate with the Revolut Business API (OAuth/certificate flow + token refresh)
Scheduled updates at regular intervals (time-driven trigger) + optional manual “Refresh now” button

Pull and populate:

Account balances (per account/currency) to a defined tab (e.g. “Balances”)
Transaction history to a defined tab (e.g. “Transactions”)
Incremental sync + de-duplication (avoid duplicates; handle status changes where applicable)
Basic logging and error handling (e.g. “Sync_Log” tab)
Secure handling of secrets (Apps Script Properties; no tokens in sheet cells)

Ideal Skills

Strong Google Sheets + Google Apps Script experience
API integration experience (OAuth/token refresh, pagination, retries)
Familiarity with or ability to understand Revolut Business API objects (accounts, transactions)
Data integration/automation background (clean schemas, reliable scheduled jobs)