As per Captain Sim software licensing agreement: You may install and use ONE copy of the software on the licensed device. Since May 2021 we have been introducing new licensing system which enforces the 'one copy' rule.

Re-install on the same device
No software deactivation required if you do not change any hardware, OS and/or username on your device.
Otherwise, you must deactivate the software (Start>Captain Sim>777 ACE 2020) before making any changes to the device.

Transfer to another device
You may uninstall the software and install it on another device for your use.  You may not do so to share this license between devices. You must deactivate the software (Start>Captain Sim>777 ACE 2020) on your first device before transfer to another device.

In your case you should install it again on the first device then deactivate.