To use Application Component LO-VCH Advanced Variant Configuration most probably you need to start scriptserver.
1650957 - Starting the Script Server
2517761 - How to add SYSTEMDB to HANA Studio in a Multitenant Database Containers (MDC) environment
2987015 - Manual installation of VCH AFL for S/4 HANA Advanced Variant Configuration S/4 Release 1909OP and following
Go with database user to terminal and run command hdbsql:
Inside enter the command:
ALTER DATABASE sd1 ADD 'scriptserver';
ALTER DATABASE SYSTEMDB ADD 'scriptserver';
ALTER SYSTEM ALTER
CONFIGURATION ('daemon.ini', 'host', ' s42021')
SET ('scriptserver','instances') = '1' WITH RECONFIGURE;
In case on the error
feature not supported: ALTER database command on SYSTEMDB only SQLSTATE: HY000
The next note is applicable:
2804287 - feature not supported: Create database command on SYSTEMDB only
Resolution
Connect to the system database for creating the tenant database.
On SAP HANA Studio:
Create a connection to SYSTEMDB
Retry the command.
With HDBSQL:
Connect to hdbsql by using the parameter "-d SYSTEMDB"
Confirm that it's connected to the SYSTEMDB by checking the hdbsql prompt:
hdbsql SYSTEMDB=>
Retry the command.
In my case the command looks like there (run after hdbsql):
hdbsql=> \c -d SYSTEMDB
-u SYSTEM -p <PASSWORD_HERE>
Add SYSTEMDB to SAP HANA Studio
Related topics
Create Tenant Database for SAP HANA Express – by the SAP HANA Academy | SAP Blogs
https://youtu.be/DbaO_-Hlq98