Expense - Sender can merge receiver's expense in IOU report

[mitarachim]

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Version Number: 9.1.91-0
Reproducible in staging?: Yes
Reproducible in production?: N/A - new feature, doesn't exist in prod
If this was caught during regression testing, add the test name, ID and link from TestRail: #65596
Email or phone of affected tester (no customers): jsdknjsoisd@gmail.com
Issue reported by: Applause Internal Team
Device used: Mac 15.5 / Chrome
App Component: Money Requests

Action Performed:

1. Go to staging.new.expensify.com
2. [User A] Send an expense to User B.
3. [User B] Send another expense to User A.
4. [User A] Open expense from User B.
5. [User A] Click More > Merge.
6. [User A] Select User A's expense.
7. [User A] Select User A's amount > Continue.
8. [User A] Click Merge expenses.

Expected Result:

User A should not be able to merge with User B's expense because User A cannot modify User B's expense.

Actual Result:

User A is able to merge with User B's expense because User A cannot modify User B's expense.
After merging expense, LHN preview shows negative amount.

Workaround:

Unknown

Platforms:

• Android: App
• Android: mWeb Chrome
• iOS: App
• iOS: mWeb Safari
• iOS: mWeb Chrome
• Windows: Chrome
• MacOS: Chrome / Safari
• MacOS: Desktop

Screenshots/Videos

Bug6911011_1754621457476.20250808_104753.mp4

View all open jobs on GitHub

[github-actions]

👋 Friendly reminder that deploy blockers are time-sensitive ⏱ issues! Check out the open `StagingDeployCash` deploy checklist to see the list of PRs included in this release, then work quickly to do one of the following:

1. Identify the pull request that introduced this issue and revert it.
2. Find someone who can quickly fix the issue.
3. Fix the issue yourself.

[melvin-bot]

Triggered auto assignment to @neil-marcellini (DeployBlockerCash), see https://stackoverflowteams.com/c/expensify/questions/9980/ for more details.

[melvin-bot]

Triggered auto assignment to @zanyrenney (Bug), see https://stackoverflow.com/c/expensify/questions/14418 for more details. Please add this bug to a GH project, as outlined in the SO.

[melvin-bot]

💬 A slack conversation has been started in #expensify-open-source