SAP Message RSENQ009 - Lock in lock manager could not be set -> long text

Diagnosis
The lock in the lock manager could not be set.
An attempt is being made to set the lock in include LRSENQF00 in the
form set_enqueue.
The lock table is table RSENQ_PROT_ENQ.
An attempt was made to lock the following object:
User/Object = &V1&
Object_typ/Action = &V2&
Subobject = &V3&
SubSubObject = &V4&