All selectors

Uniswap V3 core

0xa1bf7886: LOK

error LOK()

What it means

A transaction that reverts with the raw data 0xa1bf7886 hit the custom error LOK, defined in Uniswap V3 core. The explorer shows the hex because it does not have the contract's ABI to translate it.

The pool's reentrancy lock: the pool was entered again before the first operation finished. V3's compact equivalent of a reentrant-call revert.

How to fix it

Retry the trade on its own. If a complex route keeps hitting it, simplify the route or trade directly on the pool's own interface.

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More Uniswap V3 core errors

0x2bc80f3aT

Every selector on this page was computed as the first 4 bytes of keccak256 of the signature shown. A selector identifies a signature exactly; on rare occasions two different signatures share one, so the transaction decoder is always the more precise answer.