Hi,
If you use the e-commerce plug-in, you can have a look there: Product purchase tracking with Tag Manager - Tag Manager - Matomo forums
If not, you can:
- either use the datalayer variable in your event (defined in the tag manager e.g. Event Name =
{{otherKey}}Event Value ={{orderTotal}}) - or use the action custom dimensions (Administration cog > Measurables > Custom Dimensions). In such scenario, don’t forget to update the Matomo configuration variable in the MTM to take the custom dimensions into account.