What do the warnings in acid water stripping simulation mean?

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Hello everyone, I am working on an acidic water stripping unit, and I keep getting the following warnings: ** WARNING ** Bubble point FLASH DID NOT SOLVE. Final Temperature(K)= 1, Pressure(KPa)= 247.72, LFRAC= 1, Function= 1.139, Tolerance= 1E-5. (A Dew or Bubble flash in the supercritical region is an arbitrary phase change that is expected to fail.) ** WARNING ** TVP calculations did not converge for STREAM 8, ‘SG1’. The property method used is “sour”; could you let me know what causes these two warnings? Thank you all. The following is the keyword file: $ Generated by PRO/II Keyword Generation System $ Generated on: Wed Mar 09 11:15:21 2016 TITLE DIMENSION METRIC, STDTEMP=0, STDPRES=1.03323 SEQUENCE SIMSCI CALCULATION RVPBASIS=APIN, TVP=37.778 COMPONENT DATA LIBID 1,NH3/2,H2S/3,CO2/4,H2O, BANK=SIMSCI,PROCESS ASSAY CONVERSION=API94, CURVEFIT=CURRENT, KVRECONCILE=TAILS THERMODYNAMIC DATA METHOD SYSTEM(VLLE)=SOUR, SET=SOUR01, DEFAULT METHOD SYSTEM(VLLE)=GPSA, SET=GPSA01 STREAM DATA PROPERTY STREAM=FEED0, TEMPERATURE=40, PRESSURE=3, PHASE=M, & RATE(M)=4239.5, COMPOSITION(M)=1,0.4647/2,0.4537/4,99.0816 UNIT OPERATIONS SPLITTER UID=SP1 FEED FEED0 PRODUCT M=FEEDC, M=FEED1 OPERATION OPTION=FILL SPEC STREAM=FEED1, RATE(WT,KG/H),TOTAL,WET, VALUE=75000 HX UID=E5101 HOT FEED=FEED1, M=FD8 OPER HTEMP=96.723 COLUMN UID=T1 PARAMETER TRAY=24,SURE=41 FEED FD8,7/FEEDC,3 PRODUCT OVHD(M)=SG1, BTMS(M)=TW1,4185.79 DUTY 1,24,5.5363,REBOILER DUTY 2,1,-2.7,PAROHC1 PA NAME=PA1, FROM=5, TO=1, PHASE=L, DNAME=PAROHC1, PRES=2.2, & RATE(WT)=184000 PSPEC PTOP=2.2, DPCOLUMN=0.5 PRINT PROPTABLE=PART SPEC ID=COL1SPEC1, TRAY=1, TEMPERATURE(C), VALUE=90 SPEC ID=COL1SPEC2, STREAM=TW1,PPM(WT), COMP=1,WET, VALUE=80 VARY DNAME=REBOILER,PAROHC1 REBOILER TYPE=KETTLE METHOD SET=SOUR01 END