Migrateing to umi from js giving MissingEditionAccount error

[GrimLothar]

Hey! I'm migrating my old metaplex JS code to UMI. This was my old code to update an NFT's metadata with JS:

    const signerAccount = web3.Keypair.fromSecretKey(new Uint8Array(JSON.parse(keypair.secret_key)))
    const metaplex = Metaplex.make(solConnection).use(keypairIdentity(signerAccount))
    const mintKey = new web3.PublicKey(mint);
    try{
        const nft = await metaplex.nfts().findByMint(mintKey);
        const { nft: updatedNft, transactionId } = await metaplex.nfts().update(nft, {
            uri: uri,
        });
        console.log(`Successfully updated metadata URL`)
        return transactionId
    } catch (e) {
        console.error(e)
    }  

And this is the new one with UMI:

    const signerAccount = web3.Keypair.fromSecretKey(new Uint8Array(JSON.parse(keypair.secret_key)))
    const umi = await createUmiInstance(signerAccount, solConnection.rpcEndpoint);
    const mintKey = new web3.PublicKey(mint);
    try{
        const mintAddress = fromWeb3JsPublicKey(mintKey);
        const initialMetadata = await fetchMetadataFromSeeds(umi, { mint: mintAddress });
        const request = await updateV1(umi, {
            mint: mintAddress,
            authority: umi.payer,
            data: { ...initialMetadata, uri: uri },
        }).sendAndConfirm(umi);

        console.log(`Successfully updated metadata URL`);

        return bs58.encode(Buffer.from(request.signature));
    } catch (e) {
        console.error(e)
    }

The JS one is working as expected, but the UMI one is throwing this error:

      'Program metaqbxxUerdq28cj1RbAWkYQm3ybzjb6a8bt518x1s invoke [1]',
      'Program log: IX: Update',
      'Program log: Auth type: Metadata',
      'Program log: This mint account has an edition but none was provided.',
      'Program metaqbxxUerdq28cj1RbAWkYQm3ybzjb6a8bt518x1s consumed 21230 of 200000 compute units',
      'Program metaqbxxUerdq28cj1RbAWkYQm3ybzjb6a8bt518x1s failed: custom program error: 0x6c'

What am I missing?

Thanks!