A page loading might be slow. Depending on the number of items in the Cart, it may take more than 20 seconds to load.
To resolve the issue, download and install the hotfix:
For Sitecore XC 9.0.1: Commerce/SC Hotfix 287501-1 CommerceEngine.2.1.57.zip
Be aware that the hotfix was built for a specific Sitecore XC version, and must not be installed on other Sitecore XC versions or in combination with other hotfixes. In case any other hotfixes have already been installed on a certain Sitecore XC instance, send a request for a compatibility check to Sitecore Support.
Note that the ZIP file contents need to be extracted to locate installation instructions and related files inside. The hotfixes must be installed on a CM instance and then synced with other instances using standard development practices.