Why did my contact get removed in Accounts Receivable when I deleted it from an account in Sales?

If you've synced them between the two applications, then account contacts are visible in both Oracle Financials, including Accounts Receivable, and in Oracle Sales systems. If an organization record is shared between a customer in Accounts Receivable and an account in Sales, then Sales and Financials both have access to it.

Note: Whether a user has access to see account data is based on security settings for the user.

Here are some configurations that can prevent a user with a Sales security role from deleting a contact or removing a contact from an account: