Does anyone see something wrong with this code?. I cant seem to get it to set the sublist value. I do get the log on the block where it is setting it but no change on the UI. This is deployed on item fulfilments

function setData(asnInfo, context) {
    const fn = 'setData';
    log.audit({ title: fn, details: 'Start...' });
    const rec = context.newRecord;
    const lineCount = rec.getLineCount({ sublistId: 'item' });

    if (lineCount > 0) {
      for (let i = 0; i < lineCount; i += 1) {
        const itemId = rec.getSublistValue({
          sublistId: 'item',
          fieldId: 'item',
          line: i,
        });
        log.audit({ title: 'itemId', details: itemId });
        if (asnInfo[itemId]) {
          Object.keys(asnInfo[itemId]).forEach((el) => {
            if (el !== 'itemName') {
              log.audit({ title: 'setting data', details: `fieldId: ${el} - value: ${asnInfo[itemId][el]}` });
              try {
                rec.setSublistValue({
                  sublistId: 'item',
                  fieldId: el,
                  line: i,
                  value: asnInfo[itemId][el],
                });
              } catch (e) {
                log.error({ title: 'ERROR', details: e });
              }
            }
          });
        }
      }
    }
  }

basics are to do this beforeSubmit

Oh yeah, this is on a beforeSubmit

honestly, I wouldn't expect this logic to scale well, item is very bad in the uniqueness department

really? I just want to set some custom columns based on some information from the items

otherwise I recommend not being fancy and start hardcoding the fields you want to set, then move onto using asnInfo

oh I see what you mean!

Why can’t you just source the item info using source settings from your custom column field?

Because the value it is from the item but from a custom record, so Im looking the SO and the related custom record (asn) So I have an Item123 on the ASN Data for SO1, but that same item info can be different on another SO.