# API error after update to 2.16.0
**URL:** https://forum.mautic.org/t/api-error-after-update-to-2-16-0/13349
**Category:** Product Support
**Created:** [March 12, 2020, 5:09pm UTC](https://forum.mautic.org/t/api-error-after-update-to-2-16-0/13349 "2020-03-12T17:09:41Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@leonsmit](https://forum.mautic.org/u/leonsmit)
#### Post date: [March 12, 2020, 5:09pm UTC](https://forum.mautic.org/t/api-error-after-update-to-2-16-0/13349/1 "2020-03-12T17:09:41Z")
**Your software**
My Mautic version after update is: 2.16.0
My Previous Mautic version : 2.15.3
My PHP version is: 7.2.24-0ubuntu0.18.04.3
**Your problem**
My problem is:
We have a server side app which uses Mautic API to send emails. It stopped working after updating Mautic.
Gives error 500 on “emails/{0}/contact/{1}/send” method call
These errors are showing in the log:
mautic.CRITICAL: Uncaught PHP Exception Symfony\Component\Debug\Exception\ClassNotFoundException: “Attempted to load class “IntlExtension” from namespace “Twig\Extensions”. Did you forget a “use” statement for another namespace?” at /data/www/dev.ease-software.nl/mautic/plugins/MauticAdvancedTemplatesBundle/Helper/TemplateProcessor.php line 65 {“exception”:"[object] (Symfony\Component\Debug\Exception\ClassNotFoundException(code: 0): Attempted to load class “IntlExtension” from namespace “Twig\Extensions”.\nDid you forget a “use” statement for another namespace? at /data/www/dev.ease-software.nl/mautic/plugins/MauticAdvancedTemplatesBundle/Helper/TemplateProcessor.php:65)"}
Steps I have tried to fix the problem:
Clearing cache folder
Updating DB schema
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### Author:  [@mayanktiwaridotcom](https://forum.mautic.org/u/mayanktiwaridotcom)
#### Post date: [March 14, 2020, 1:19pm UTC](https://forum.mautic.org/t/api-error-after-update-to-2-16-0/13349/2 "2020-03-14T13:19:01Z")
> [@leonsmit](#):
>
> IntlExtension
looks like the problem is in PHP extension and not with mautic, please check if your server have php-intl extension installed and enabled.
you can check this by going in mautic settings \> system info.
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### Author:  [@leonsmit](https://forum.mautic.org/u/leonsmit)
#### Post date: [March 17, 2020, 11:09am UTC](https://forum.mautic.org/t/api-error-after-update-to-2-16-0/13349/3 "2020-03-17T11:09:57Z")
It is installed.
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### Author:  [@mayanktiwaridotcom](https://forum.mautic.org/u/mayanktiwaridotcom)
#### Post date: [March 17, 2020, 1:43pm UTC](https://forum.mautic.org/t/api-error-after-update-to-2-16-0/13349/4 "2020-03-17T13:43:31Z")
Okay,
Just to be sure can you please run `composer install` in your mautic root. this will ensure if there is any missing extension it’ll be installed. Mautic uses `symfony/intl` package to provide support for intl extension. so in case this extension is available with php but its symfony wrapper is missing it’ll be installed.
[https://packagist.org/packages/symfony/intl](https://packagist.org/packages/symfony/intl) basically this seems to be missing. Also you this problem is being caused by MauticAdvancedTemplatesBundle and as per [https://github.com/Logicify/mautic-advanced-templates-bundle](https://github.com/Logicify/mautic-advanced-templates-bundle) repository it is not tested with mautic 2.16.0 and php 7.2.
Just in case `composer install` doesn’t fix the issue please raise an issue on the repository link.
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### Author:  [@leonsmit](https://forum.mautic.org/u/leonsmit)
#### Post date: [March 24, 2020, 1:06pm UTC](https://forum.mautic.org/t/api-error-after-update-to-2-16-0/13349/5 "2020-03-24T13:06:45Z")
> composer install
> That helped. Thank you.