MediaWiki internal error.

Original exception: [ZgWjdh4qrMb415Yh8aubpQAAAFc] /index.php?title=Indication_for_PCI&action=edit&oldid=744 TypeError: Unsupported operand types: string * int
Backtrace:
from /var/www/vhosts/pcipedia.org/httpdocs/includes/shell/Command.php(100)
#0 /var/www/vhosts/pcipedia.org/httpdocs/includes/shell/CommandFactory.php(168): MediaWiki\Shell\Command->limits()
#1 /var/www/vhosts/pcipedia.org/httpdocs/includes/shell/Shell.php(129): MediaWiki\Shell\CommandFactory->create()
#2 /var/www/vhosts/pcipedia.org/httpdocs/includes/GlobalFunctions.php(1686): MediaWiki\Shell\Shell::command()
#3 /var/www/vhosts/pcipedia.org/httpdocs/includes/GlobalFunctions.php(1724): wfShellExec()
#4 /var/www/vhosts/pcipedia.org/httpdocs/includes/media/BitmapHandler.php(273): wfShellExecWithStderr()
#5 /var/www/vhosts/pcipedia.org/httpdocs/includes/media/JpegHandler.php(196): BitmapHandler->transformImageMagick()
#6 /var/www/vhosts/pcipedia.org/httpdocs/includes/media/TransformationalImageHandler.php(253): JpegHandler->transformImageMagick()
#7 /var/www/vhosts/pcipedia.org/httpdocs/includes/filerepo/file/File.php(1316): TransformationalImageHandler->doTransform()
#8 /var/www/vhosts/pcipedia.org/httpdocs/includes/filerepo/file/File.php(1263): File->generateAndSaveThumb()
#9 /var/www/vhosts/pcipedia.org/httpdocs/extensions/PageImages/includes/PageImages.php(277): File->transform()
#10 /var/www/vhosts/pcipedia.org/httpdocs/includes/HookContainer/HookContainer.php(160): PageImages\PageImages->onBeforePageDisplay()
#11 /var/www/vhosts/pcipedia.org/httpdocs/includes/HookContainer/HookRunner.php(946): MediaWiki\HookContainer\HookContainer->run()
#12 /var/www/vhosts/pcipedia.org/httpdocs/includes/OutputPage.php(2871): MediaWiki\HookContainer\HookRunner->onBeforePageDisplay()
#13 /var/www/vhosts/pcipedia.org/httpdocs/includes/MediaWiki.php(922): OutputPage->output()
#14 /var/www/vhosts/pcipedia.org/httpdocs/includes/MediaWiki.php(562): MediaWiki->main()
#15 /var/www/vhosts/pcipedia.org/httpdocs/index.php(50): MediaWiki->run()
#16 /var/www/vhosts/pcipedia.org/httpdocs/index.php(46): wfIndexMain()
#17 {main}

Exception caught inside exception handler: [ZgWjdh4qrMb415Yh8aubpQAAAFc] /index.php?title=Indication_for_PCI&action=edit&oldid=744 TypeError: Unsupported operand types: string * int
Backtrace:
from /var/www/vhosts/pcipedia.org/httpdocs/includes/shell/Command.php(100)
#0 /var/www/vhosts/pcipedia.org/httpdocs/includes/shell/CommandFactory.php(168): MediaWiki\Shell\Command->limits()
#1 /var/www/vhosts/pcipedia.org/httpdocs/includes/shell/Shell.php(129): MediaWiki\Shell\CommandFactory->create()
#2 /var/www/vhosts/pcipedia.org/httpdocs/includes/GlobalFunctions.php(1686): MediaWiki\Shell\Shell::command()
#3 /var/www/vhosts/pcipedia.org/httpdocs/includes/GlobalFunctions.php(1724): wfShellExec()
#4 /var/www/vhosts/pcipedia.org/httpdocs/includes/media/BitmapHandler.php(273): wfShellExecWithStderr()
#5 /var/www/vhosts/pcipedia.org/httpdocs/includes/media/JpegHandler.php(196): BitmapHandler->transformImageMagick()
#6 /var/www/vhosts/pcipedia.org/httpdocs/includes/media/TransformationalImageHandler.php(253): JpegHandler->transformImageMagick()
#7 /var/www/vhosts/pcipedia.org/httpdocs/includes/filerepo/file/File.php(1316): TransformationalImageHandler->doTransform()
#8 /var/www/vhosts/pcipedia.org/httpdocs/includes/filerepo/file/File.php(1263): File->generateAndSaveThumb()
#9 /var/www/vhosts/pcipedia.org/httpdocs/extensions/PageImages/includes/PageImages.php(277): File->transform()
#10 /var/www/vhosts/pcipedia.org/httpdocs/includes/HookContainer/HookContainer.php(160): PageImages\PageImages->onBeforePageDisplay()
#11 /var/www/vhosts/pcipedia.org/httpdocs/includes/HookContainer/HookRunner.php(946): MediaWiki\HookContainer\HookContainer->run()
#12 /var/www/vhosts/pcipedia.org/httpdocs/includes/OutputPage.php(2871): MediaWiki\HookContainer\HookRunner->onBeforePageDisplay()
#13 /var/www/vhosts/pcipedia.org/httpdocs/includes/exception/MWExceptionRenderer.php(183): OutputPage->output()
#14 /var/www/vhosts/pcipedia.org/httpdocs/includes/exception/MWExceptionRenderer.php(102): MWExceptionRenderer::reportHTML()
#15 /var/www/vhosts/pcipedia.org/httpdocs/includes/exception/MWExceptionHandler.php(131): MWExceptionRenderer::output()
#16 /var/www/vhosts/pcipedia.org/httpdocs/includes/exception/MWExceptionHandler.php(248): MWExceptionHandler::report()
#17 /var/www/vhosts/pcipedia.org/httpdocs/includes/MediaWiki.php(584): MWExceptionHandler::handleException()
#18 /var/www/vhosts/pcipedia.org/httpdocs/index.php(50): MediaWiki->run()
#19 /var/www/vhosts/pcipedia.org/httpdocs/index.php(46): wfIndexMain()
#20 {main}