Daily low fever in 98 to 99. 8 from

Since 2 mnths temp varies from 97.6 to 99.8 ,earlier it is normal ,I'm 24 yrs male ,first widal done o& h titres 1:40 temperature varies between 98 to 99.8 after 5 days widal o&h 1:160 ah,bh 1:20, taken antiboitics like gudcef ,ornio, azithromycin, moxinow, doxt-xl,for 14 days,widal o&h 1:40 but fever pattern is same,morning after 9am increases to 99 ,after noon goes to 99.4 sometimes 99.8 night after 10 pm comes to normal,10 days again went to doctor,blood tests smear for mp negative,chest x ray normal,us abdomennormal, mantoux-ve,CRP 6,ESR 10 ,earlier 2 mnth back it is 26 10daysbackitis 10,scrub thypus -ve,RF assay negative, thyroid normal,blood culture negative, thypoid iggigmnegative, antioiotics stopped 1 mnth back,what is the reason for this fever,visted 5 doctors(md gen med)saying that it is normal no need to worry due to tension or stress some harmones are released, mine appetite is good , having headache,sir i want suggestion,fever continuing from2mnths istyhpoidor vitam defic