Liquid detected in USB-C port

Apple has published an official support document confirming that certain MacBook models can display an alert when liquid is detected in a USB-C port.

Apple Support: If you see a liquid-detection alert on your MacBook Neo, MacBook Air, or MacBook Pro

Direct URL: If you see a liquid-detection alert on your MacBook Air or MacBook Pro - Apple Support (CA)

According to Apple, this feature is available on supported MacBook Air and MacBook Pro models, as well as the MacBook Neo, running macOS Sequoia or later.

The alert may appear when a USB-C cable or accessory is connected and liquid is detected in the port, cable, or accessory.

Apple cautions that charging while a USB-C port is wet can cause corrosion, permanent damage, or connectivity issues.

Important distinction: This document confirms that Apple recognizes liquid-detection alerts on certain Mac laptops.

However, the feature is not available on every MacBook model, and the appearance of an alert does not, by itself, establish that liquid damage has occurred.

If the laptop was just repaired and you noticed the issue right away, then the repair should be covered under the previous damage repair (depends on whether the repair was a mail-in or just replacing individual components in the store's repair shop).

If any significant amount of time has transpired since the damage repair, then Apple may consider as new damage. All you can do is inquire at the place you had it repaired to find out. Technically the USB-C port is inexpensive, but it could require extensive labor to access it depending on the exact model (some USB-C ports can be removed easily while others require removal of the Logic Board).

Sounds like the repair shop didn't properly inspect the USB-C ports during the repair. I have seen so many dirty & damaged USB-C ports that I always inspect them no matter why a laptop arrives for repair. If you get no satisfaction, then speak with the manager. If still no satisfaction, then you may need to contact Apple directly...I doubt Apple support will do anything to help...so you may be contacting Apple corporate to let them know your dissatisfaction with the repair team not catching the damaged port. Be calm & polite. I would even offer to pay for the actual part (should be about $15 US) & have them cover the additional labor since it was their fault, but if it was a mail-in repair the Apple agent may not have much they can do (a store manager especially at an Apple Store has a lot more leeway is making exceptions than an AASP does).

I highly recommend people test everything with their device after a repair to make sure every major component is working including built-in cameras, WiFi, Bluetooth, and all ports. Reporting an issue right away will usually be covered under the previous repair as it is less likely an accident occurred the same day of getting the device back home.

Did Apple repair the port with the problem? Repairs do have a guarantee. Take it back to Apple for examination. Sounds to me like the repair process failed to reset the error message.