Found the problem :
I had CP=OFF in my NATPARMS :
NTPRM FNR=300, NTPRM System File X
ABLOG=ON, .Log errors to message log X
ADAACBX=OFF, Adabas Control Block X
ADAMODE=2, .Two Adabas UQE are used X
ADANAME=ADABAS, ADA-Link-Routine X
ATTN=ON, .ATTN key support X
AUTO=OFF, .Auto logon to *INIT-USER X
BSIZE=0, .Entirex Buffer size X
CC=ON, .Terminate for error condition X
CDYNAM=100, .Number of Dynamic loads X
CF=‘%’, Terminal Command Char.X
CSTATIC=(CMMSG, Standard CSTATICS X
NSPPFUNC), DUMMY-CSTATIC X
CP=ON, Def Code Page Name X
DATSIZE=512, .Local DATA buffer size X
DBCLOSE=OFF, .No explicit CLOSE command X
DBID=001, . Default DBDID X
DBGERR=OFF, .No automatic debugger on err X
DBOPEN=OFF, .No automatic OPEN command X
DBUPD=ON, .Database updating ON X
DELETE=ON, .DELETE dynamic loaded pgms X
DFOUT=S, Output Format of Date X
DFSTACK=S, Date-Format in Stack X
DSIZE=0, .DEBUG log buffer X
DTFORM=I, .Default date format YYYY-MM-DDX
ENDBT=ON, .Auto BT at session end X
ESIZE=130, .Size of Natural editor source X
ET=ON, .Send ET/BT to all ref Dbid’s X
ETEOP=OFF, .Implicit ET at end of Nat pgm X
ETID=OFF, .No Adabas user name X
ETIO=OFF, .No ET on terminal I/O X
FDIC=(,304), .Natural Dictionary X
FNAT=(,300), .Natural System file X
FPROF=(,302), .Natural PROFILE parameters X
FREG=(,305), .Natural concurrent sessions X
FSEC=(,307), .Natural security file X
FUSER=(,301), .Natural user file X
IMSG=ON, .Session initialization errors X
INTENS=1, .Intensified over print count X
ISIZE=16, .Initialization Buffer size X
ITERM=OFF, .Initialization term on error X
LC=OFF, .No translation of lower to Up X
LE=ON, .Give error msg for DB loop limX
LS=250, .Line size default X
LT=0, .Database loop limit X
MADIO=0, .Max Ada calls between scr IO X
MAXCL=0, .Max PGM calls between scr IO X
MAXROLL=0, .Calls before roll in CICS X
MENU=OFF, .Natural Menu mode OFF X
ML=B, .Pos of MENU line X
MONSIZE=0, .SYSTP monitor buffer size X
MP=0, .MAx pages for a report X
MSGSF=ON, .Display error msg in FULL X
MT=0, .Max CPU for a Natural pgm X
NAFSIZE=0, .Buffer for Nat Advance FacilitX
NC=OFF, .No Nat system commands OFF X
NUCNAME=NATNUC00, .Nat env independant nucleus X
O4I=OFF, .Generate Opt buffer data X
PC=(OFF,NAM), .Nat Connection OFF X
PD=50, .Limit for NATPAGE facility X
PDPSIZE=512, .Profiler Data Pool - Nat ONE X
PECK=L, .Syntax check all the source X
PLOG=ON, .Log DYNparms to CMPLOG/CMPRINTX
PROFILE=, Profile Batch X
PS=80, .Page size default X
RCA=(SAGICU), .Static modules in NATNUC00 X
RCFIND=ON, .Ada rsp 113 stops program X
RCGET=ON, .Ada rsp 113 stops program X
RDCSIZE=0, .Natural Data collector X
RECAT=OFF, .No recat if GDA is wrong X
REINP=OFF, .No auto REINPUT statement X
RFILE=SPAD, FNAT/FUSER .File for recordings- RecordingX
RI=OFF, .No auto release of hold ISN X
RJESIZE=8, .Buffer for NATRJE X
ROSY=OFF, .System files read only X
RUNSIZE=16, .Run size buffer in K X
SELUNIT=(U01=OFF,U02=OFF,U03=OFF, Activate Features X
U04=OFF,U05=OFF,U06=OFF,U07=OFF,U08=OFF,U09=OFF,U10=OFF,X
U11=OFF,U12=OFF,U13=OFF,U14=OFF,U15=OFF,U16=OFF,U17=OFF,X
U18=OFF,U19=OFF,U20=OFF,U21=OFF,U22=OFF,U23=OFF, X
U24=OFF), X
SKEY=OFF, .Storage key of CICS pgm X
SL=72, .Source line length X
SLOCK=SPOD, .Source locking in MIX env X
SRETAIN=ON, .Retain CodePage of Source X
SSIZE=64, .Size of edit work area X
STACK=OFF, .Initial Natural command X
STEPLIB=SYSTEM, .Additional Natural Steplib X
SUBSID=NAT9, .Default Natural Sub-system X
SYNERR=ON, .Syn errors are passed to ETP X
TD=AUTO, .Local time X
THSIZE=0, .Batch Thread size X
TMODEL=0, .IBM 3270 model X
TSIZE=0, .Adabas text retrieval buffer X
UCONMAX=0, .Max user sessions for Nat ONE X
ULANG=1, .Default language code X
WH=OFF, .Wait for records in HOLD ? X
WPSIZE=(32,128,2097151,2097151), SZ Below,above,mbot,btoX
XREF=ON, .Predict XREF on X
ZD=ON, .Zero division check x
ZP=ON, .Only print one zero x
ZSIZE=0 .Size of Entire DB