TIDA-00913: More than two FAST observers running at the same time?

Part Number: TIDA-00913

Hi, I'm using Intanspin-FOC for an application with more than two motors. Motor 1 and 2 are spinning correctly, but when I try to start a third observer using "obj->estHandle = EST_initEst(MTR_3);", it doesn't work. Is there a limit on the number of motors that can be used? Is there a way to use three FAST estimators simultaneously?