diff --git a/openair1/PHY/NR_UE_TRANSPORT/nr_ulsch_ue.c b/openair1/PHY/NR_UE_TRANSPORT/nr_ulsch_ue.c
index 5957324659..e7e02520d6 100644
--- a/openair1/PHY/NR_UE_TRANSPORT/nr_ulsch_ue.c
+++ b/openair1/PHY/NR_UE_TRANSPORT/nr_ulsch_ue.c
@@ -401,6 +401,10 @@ uint8_t nr_ue_pusch_common_procedures(PHY_VARS_NR_UE *UE,
 #endif
 
   tx_offset = slot*frame_parms->samples_per_slot - timing_advance;
+
+  if (tx_offset < 0)
+    tx_offset += frame_parms->samples_per_frame;
+
   txdata = UE->common_vars.txdata;
   txdataF = UE->common_vars.txdataF;