diff --git a/mission/controller/acs/MultiplicativeKalmanFilter.cpp b/mission/controller/acs/MultiplicativeKalmanFilter.cpp
index efa74568..647e2141 100644
--- a/mission/controller/acs/MultiplicativeKalmanFilter.cpp
+++ b/mission/controller/acs/MultiplicativeKalmanFilter.cpp
@@ -1079,7 +1079,7 @@ ReturnValue_t MultiplicativeKalmanFilter::mekfEst(
   MatrixOperations<double>::add(*cov0, *cov1, *initialCovarianceMatrix, 6, 6);
 
   if (not(VectorOperations<double>::isFinite(propagatedQuaternion, 4)) ||
-      not(MatrixOperations<double>::isFinite(initialQuaternion, 6, 6))) {
+      not(MatrixOperations<double>::isFinite(*initialCovarianceMatrix, 6, 6))) {
     updateDataSetWithoutData(mekfData, MekfStatus::NOT_FINITE);
     return MEKF_NOT_FINITE;
   }