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### Description

We would use **www_challenge** method of **auth** module on our kemi lua script. Function is not mapped on [auth kemi](https://kamailio.org/docs/tutorials/5.3.x/kamailio-kemi-framework/modules/#a...) so we tried to use [modf](https://kamailio.org/docs/tutorials/5.3.x/kamailio-kemi-framework/kemimods/#...) but we have every time this log

``` app_lua [app_lua_api.c:1725]: sr_kemi_lua_modf(): function 'www_challenge' has fixup - cannot be used ```

We tried this call to the method on lua script

``` KSR.x.modf("www_challenge", realm, 1); ```

The question is: are we calling method on a bad way or is not possible to call www_challenge method by kemi lua ?

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### Troubleshooting

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### Possible Solutions

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### Additional Information

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