diff --git a/src/host/dmr/lookups/DMRAffiliationLookup.cpp b/src/host/dmr/lookups/DMRAffiliationLookup.cpp
index f0010b20..336e59fa 100644
--- a/src/host/dmr/lookups/DMRAffiliationLookup.cpp
+++ b/src/host/dmr/lookups/DMRAffiliationLookup.cpp
@@ -61,12 +61,12 @@ bool DMRAffiliationLookup::grantChSlot(uint32_t dstId, uint32_t srcId, uint8_t s
         return false;
     }
 
-    __lock();
-
     if (getAvailableSlotForChannel(chNo) == 0U || chNo == m_tsccChNo) {
         m_chLookup->removeRFCh(chNo);
     }
 
+    __lock();
+
     m_grantChTable[dstId] = chNo;
     m_grantSrcIdTable[dstId] = srcId;
     m_grantChSlotTable[dstId] = std::make_tuple(chNo, slot);