1.- I would like to ask you to follow this steps:
- Go to Woocommerce -> Woocommerce Multilingual -> Settings tab -> Select the 'Synchronize cart content when switching languages' options -> Save the changes.
- Go to WPML -> Languages -> Activate the Ajax cookie -> Save the changes.
Could you confirm that the issue is solved?
2.- Please update all outdated plugins and themes, specially WPML plugins. Outdated functionalities can cause conflicts in the code.