The message says:
SQL1390C The environment variable DB2INSTANCE is not defined or is invalid.
and the SQL10007 is also returned because of this – so fix the DB2INSTANCE by setting it to your current instance.
Addition: Your driver seetting within DBeaver should point to the correct location of following files: db2java.zip db2jcc_license_cu.jar (or similar) db2jcc4.jar
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