How To Regularize The Period?

hi This is kutty sending a message regarding my sister has periods delayed problem.she is 32 old.height is 168 cm,weight is 65kg.she went to consult a lady doctor at CMC at vellore,South India she advised that she has been using devery tablet 10mg.till she got some health illness due to cold ,fever, chest pain and clotted bleeding .could you pls advise me to recover from this.