It is not stipulated that fasts be observed consecutively for one who cannot find a hadiy

Praise be to Allah.

It is permissible for the seven days mentioned in the verse (interpretation of the meaning): “and seven days after his return (to his home)” [al-Baqarah 2:196] to be observed either consecutively or separately. 

And Allah is the source of strength; may Allah send blessings and peace upon our Prophet Muhammad and his family and Companions. End quote. 

Standing Committee for Academic Research and Issuing Fatwas. 

Shaykh ‘Abd al-‘Azeez ibn ‘Abd-Allaah ibn Baaz, Shaykh ‘Abd al-Razzaaq ‘Afeefi, Shaykh ‘Abd-Allaah ibn Ghadyaan, Shaykh ‘Abd-Allaah ibn Qa’ood