SQL Server on CentOS using CAL licensing
Yes, the wrong SQL Server installation files (for the CAL-based setup) were used. The 20-core-limit version is designed for people upgrading from older versions of SQL Server, as explained by Aaron Bertrand.

Check with the team who got your installation files for SQL Server (ISO, CD, ZIP, etc) to get the core-based installation files instead of CAL-based installation files.

Microsoft's instructions for Linux don't include CentOS, but if you read through the comments on that page, they tell you how to pick your repo. If you're still using the latest CU repo and you're still getting the issue, then contact Microsoft support - they may have deployed the wrong binaries to the repo. (This wouldn't be something an outsider could fix.)