Preliminary Manipulations
Before exploring the problems listed below, proceed with these preliminary checks:
Clear your store's cache from the menu Advanced settings > Performance
Create a basic rule, for example, a shipping fee of €10, without any condition.
If this rule is applied in the front, then check the conditions of your rules.
Some conditions (e.g., postal code) are only applied after the customer has entered the delivery address.
Module not activated
Go to Modules > Module management and make sure the module is activated.
Conflict with "overrides"
Go to Advanced settings > Performance
Ensure that the option Disable all overrides is disabled.
If there is a conflict with another module, contact our support.
Problem external to the module
Disable the module
If the problem persists, it comes from another element (third-party module, theme, etc.).
Contact our support for an in-depth analysis (this intervention may be charged).