Fatal error Matomo (5.1.2)

Hi,

I have a fatal error when I try to access Matomo reporting (5.1.2).
I’ve downgraded to 5.1.1 then updated again to 5.1.2, but the error occurs again.

Do you have any ideas of what could cause this issue?

Thanks in advance!

Here is the error log:

Une erreur de type E_ERROR a été causée dans la ligne 88 du fichier /public_html/wp-content/plugins/matomo/app/plugins/Referrers/Social.php. Message d’erreur : Uncaught Error: Class “Spyc” not found in /public_html/wp-content/plugins/matomo/app/plugins/Referrers/Social.php:88

Stack trace:

#0 /public_html/wp-content/plugins/matomo/app/plugins/Referrers/Social.php(78): Piwik\Plugins\Referrers\So/cial->loadYmlData()

#1 /public_html/wp-content/plugins/matomo/app/plugins/Referrers/Social.php(51): Piwik\Plugins\Referrers\Social->loadLocalYmlData()

#2 /public_html/wp-content/plugins/matomo/app/plugins/Referrers/Social.php(39): Piwik\Plugins\Referrers\Social->loadDefinitions()

#3 /public_html/wp-content/plugins/matomo/app/plugins/Referrers/Social.php(163): Piwik\Plugins\Referrers\Social->getDefinitions()

#4 /public_html/wp-content/plugins/matomo/app/plugins/Referrers/API.php(327): Piwik\Plugins\Referrers\Social->getMainUrlFromName()

#5 [internal function]: Piwik\Plugins\Referrers\API->Piwik\Plugins\Referrers{closure}()

#6 /public_html/wp-content/plugins/matomo/app/core/DataTable/Filter/ColumnCallbackAddMetadata.php(74): call_user_func_array()

#7 /public_html/wp-content/plugins/matomo/app/core/DataTable.php(478): Piwik\DataTable\Filter\ColumnCallbackAddMetadata->filter()

#8 /public_html/wp-content/plugins/matomo/app/plugins/Referrers/API.php(326): Piwik\DataTable->filter()

#9 [internal function]: Piwik\Plugins\Referrers\API->getSocials()

#10 /public_html/wp-content/plugins/matomo/app/core/API/Proxy.php(224): call_user_func_array()

#11 /public_html/wp-content/plugins/matomo/app/core/Context.php(27): Piwik\API\Proxy->Piwik\API{closure}()

#12 /public_html/wp-content/plugins/matomo/app/core/API/Proxy.php(140): Piwik\Context::executeWithQueryParameters()

#13 /public_html/wp-content/plugins/matomo/app/core/API/Request.php(242): Piwik\API\Proxy->call()

#14 /public_html/wp-content/plugins/matomo/app/plugins/API/ProcessedReport.php(316): Piwik\API\Request->process()

#15 /public_html/wp-content/plugins/matomo/app/plugins/API/API.php(230): Piwik\Plugins\API\ProcessedReport->getProcessedReport()

#16 [internal function]: Piwik\Plugins\API\API->getProcessedReport()

#17 /public_html/wp-content/plugins/matomo/app/core/API/Proxy.php(224): call_user_func_array()

#18 /public_html/wp-content/plugins/matomo/app/core/Context.php(27): Piwik\API\Proxy->Piwik\API{closure}()

#19 /public_html/wp-content/plugins/matomo/app/core/API/Proxy.php(140): Piwik\Context::executeWithQueryParameters()

#20 /public_html/wp-content/plugins/matomo/app/core/API/Request.php(242): Piwik\API\Proxy->call()

#21 /public_html/wp-content/plugins/matomo/app/core/API/Request.php(511): Piwik\API\Request->process()

#22 /public_html/wp-content/plugins/matomo/classes/WpMatomo/Report/Data.php(54): Piwik\API\Request::processRequest()

#23 /public_html/wp-content/plugins/matomo/classes/WpMatomo/Report/Renderer.php(100): WpMatomo\Report\Data->fetch_report()

#24 /public_html/wp-includes/shortcodes.php(434): WpMatomo\Report\Renderer->show_report()

#25 [internal function]: do_shortcode_tag()

#26 /public_html/wp-includes/shortcodes.php(273): preg_replace_callback()

#27 /public_html/wp-content/plugins/matomo/classes/WpMatomo/Admin/views/summary.php(154): do_shortcode()

#28 /public_html/wp-content/plugins/matomo/classes/WpMatomo/Admin/Summary.php(118): include(’ /…')

#29 /public_html/wp-includes/class-wp-hook.php(324): WpMatomo\Admin\Summary->show()

#30 /public_html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters()

#31 /public_html/wp-includes/plugin.php(517): WP_Hook->do_action()

#32 /public_html/wp-admin/admin.php(259): do_action()

#33 {main}

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