Hello @guongvtd ,
We are sorry you are facing this issue. Based on this blog post:
"Not all versions of the Windows Application are compatible with the PHP Library Versions. Many thanks to Adrian Calinescu for providing version information. He has made a GitHub repo which you can download and install located here: https://github.com/snobu/php-imagick-webapps These steps are for PHP v5.6, ImageMagick PHP Library 3.3.0RC2 and ImageMagick Windows Application 6.9.2.7."
Here are some alternatives you can try:
PHP 7 x64 ImageMagick 6.9.3.7 Site Extension. This can be installed through the Azure Portal or the SCM/Kudu > SiteExtensions area.
https://github.com/snobu/php-imagick-webapps for PHP 7.0 steps.
Please let us know if you have further questions.
Thanks,
Grace