DIR getting Locked during MDT execution

Dear Experts;

In our projects we use Device Infor Records (DIR).During the cretion of technical master data a MDT gets triggered which installs the DIR at the Installation.

We are facing a issue currently in our system.Whenever employee starts the process ,it gives an error message that the Material/Seral Number <DIR No> is locked by the user.

If I execute the process individually on test system it works fine.In production environment whenever there are multiple processed are triggered simultaneously then this problem occurs.

Also occurance of this issue is not consistent ,we get 2-3 such cases per day.

Kindly advice what could be the issue and how we could fix this.

regards,

Sagar