That's a known issue in WordPress Multisite, you can find this note in our documentation
IMPORTANT: WordPress Multisite requires that you use different domain names for each site. In order to make it works, we configure a transparent xip.io domain to the current IP address. Without this, you may get a "Cookies are blocked or not supported by your browser. You must enable cookies to use WordPress" error message.
Can you access your application using yourip.xip.io? We modified the configuration of Apache to start redirecting to the .xip.io domains if you try to use an IP.
We have a Support Tool that will gather relevant information for us to debug the issue. Could you please download and execute it on the machine where the stack is running by following the steps described in the guide below? You must click on the platform or cloud that you are using to find the correct instructions.
How to Run the Bitnami Support Tool
Please note that you need to paste the code outputted by the tool in your reply.