> ## Documentation Index
> Fetch the complete documentation index at: https://docs.telnesstech.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Customer Self-Service

> Enable customers to manage their own subscriptions, view usage, update plans, and handle service requests through the Seamess OS API. This use case covers building customer portal features that reduce support costs while improving customer satisfaction.

## Get Subscription

First, start out by getting the subscription of the user you want to manage.

```
TODO CODE EXAMPLE
```

## Changing plan

### Get change options for subscription

Get all available product offerings a subscription can be changed to and when the change can take effect.

When the subscription can be changed typically depends on the network setup, billing cycle, and current product offering. As a rule of thumb (though not always), upgrades and lateral moves are immediate, while downgrades take effect at the next renewal date.

```
TODO CODE EXAMPLE
```

### Change subscription product offering

When the change takes effect is dictated by what product offering is chosen, which in its place depends on the network setup, billing cycle.

```
TODO CODE EXAMPLE
```

## Managing add-ons

### Get available add-on options for subscription

Get all add-on options that are available to be added to a subscription.

```
TODO CODE EXAMPLE
```

### Add add-on to subscription

```
TODO CODE EXAMPLE
```

### Get change options for subscription add-on

```
TODO CODE EXAMPLE
```

### Change subscription add-on product offering

```
TODO CODE EXAMPLE
```

### Cancel add-on from subscription

```
TODO CODE EXAMPLE
```

## Buying top-up

```
TODO CODE EXAMPLE
```

## Get subscription usage

```
TODO CODE EXAMPLE
```