@DOMDOM4343Apologies for the inconvenience caused. Based on my understanding, the report builder requests shouldn't disappear automatically. However, in your case you have mentioned that the report builder requests has disappeared automatically. So, I will suggest you to please raise this issue to the Client Care team.
Meanwhile, if you have already scheduled the report builder request then I will suggest you to use that scheduled file & you can use that report builder report going forward.
Please let me know if you have any further questions.