# MPC signing failed for Embedded Wallets (NCW) sandbox environment

**URL:** <https://community.fireblocks.com/t/mpc-signing-failed-for-embedded-wallets-ncw-sandbox-environment/3050>\
**Category:** Developer Discussion\
**Created:** [December 19, 2025, 1:04pm UTC](https://community.fireblocks.com/t/mpc-signing-failed-for-embedded-wallets-ncw-sandbox-environment/3050 "2025-12-19T13:04:02Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![jon](https://avatars.discourse-cdn.com/v4/letter/j/3bc359/32.png) [@jon](https://community.fireblocks.com/u/jon)\
**Post date:** [December 19, 2025, 1:04pm UTC](https://community.fireblocks.com/t/mpc-signing-failed-for-embedded-wallets-ncw-sandbox-environment/3050/1 "2025-12-19T13:04:02Z")

</div>

I’m integrating Embedded Wallets. Things is working fine so far and I could generate mpc keys and sign transactions.  
But suddenly it stops working since yesterday and I could not sign transaction anymore.  
I updated the FireblockSdk for ios to the latest (2.9.14) but that doesn’t help either.

 ![image](https://us1.discourse-cdn.com/flex015/uploads/fireblocks/original/1X/1215844c726285910af2b119f26687f656467db1.png)

Then timeout and failed

Transaction id:  
`ff0e3499-a2d3-4912-998e-349203442dfe`

Source wallet id:  
`7a871ca2-2c29-420e-a62b-61eaae263255`  
My sandbox account: [thuan@bitwala.com](mailto:thuan@bitwala.com)

It worked perfectly fine for me last week so it’s a bit weird. Please help.