I looked up this message in the EDA Playground Forum, and the reply is:
“The maximum number of lines you can output from any simulation is 5000. Your simulation has exceeded this.”
This means that the output log of the simulation is too long for the EDA Playground website. Most simulation tools do not have this type of restriction.
You can avoid the error by commenting out line 53 in mem_monitor.sv:
//mem_pkt.print();//(uvm_default_line_printer);
This allows the simulation to complete without errors.