I am currently using arb, sequence filing program.

I would like to add some new species to my existing tree.

According to the tutorial, I clicked "Tree | Add Species to Existing Tree | Parsimony (quick add marked) menu"

After "Loading seqeunces " Unfortunately, It shows me the sign "It has too short sequence 0, minimum is 20" repeatedly.
Each flie has about 600 bp of sequence.. I attached the file.

It is first time using a program on the linux, I gave me many troubles and hard time..

Please help me how to solve the problem and what wrong with this situation. Thank you for your reply in advance!