Error : "Bad substitution" and "[[: not found"

[CaroleBelliardo]

Dear Developpers,

I would like to use your this software but something is wrong with my data or command line.
I try to run short_read_connector_counter with the following line :
sh ./short_read_connector_counter.sh index -b hifi_reads.fasta.gz -i hifi_reads__my_counter_index.dumped

Where y input is a classical fasta file containing hifi reads. And the sd output tell me :

./short_read_connector_counter.sh: 10: ./short_read_connector_counter.sh: [[: not found
./short_read_connector_counter.sh: 15: ./short_read_connector_counter.sh: [[: not found
./short_read_connector_counter.sh: 29: ./short_read_connector_counter.sh: function: not found
short_read_connector_counter.sh - Compare reads from two read sets (distinct or not)
Version 1.2.0
Usage: sh short_read_connector_counter.sh [index/query]
./short_read_connector_counter.sh: 34: ./short_read_connector_counter.sh: Syntax error: "}" unexpected```

Thank for your help,
Best regards. 
Carole