Error: You lack the required entitlement

Is there something familiar in server console like this?

You lack the required entitlement to use rcore_tennis

There could be a several reasons why this is happening

1. You have bought the script with other fivem account than the server's owner is

2. The server needs to be restarted

3. Your OS time may be ahead/behind of real time.

I have bought the script with annother account (1)

If this is the case, check to this guide Transfer resource guide.

I have not restarted the server

It feels like there is no need to explain this. Restart it!

Operation system doesn't have the right time?

You just need to open this website: https://time.is/ and just choose where the server is located, and if it will be ahead/behind more than one minute please correct this issue unless the problem won't be solved.

How do I sync time?