```ruby
require 'net/http'

require 'pesapal/merchant'
require 'pesapal/merchant/details'
require 'pesapal/merchant/post'
require 'pesapal/merchant/status'
require 'pesapal/oauth'
require 'pesapal/version'

require 'pesapal/railtie' if defined?(Rails)

```

Fix error cause by missing htmlentities
user
```ruby
require 'htmlentities'
require 'net/http'

require 'pesapal/merchant'
require 'pesapal/merchant/details'
require 'pesapal/merchant/post'
require 'pesapal/merchant/status'
require 'pesapal/oauth'
require 'pesapal/version'

require 'pesapal/railtie' if defined?(Rails)

```
assistant