[modeller_usage] Error in align codes

Hi, i am Yang here..

I am trying to build my model by using basic tutorial, however during build_profile, i have encountered a problem,Modeller error: read_al_373E> Protein specified in ALIGN_CODES<i> was not found in the alignment files; ALIGN_CODES< 1>= ALL, because i am looking for potential templates to my target.

I have saved my alignment file (bleg1_2439.ali) in plain text format with suffix .ali, is that affect the reading?

Your feedback is important and appreciated.. Thank you