Sequences in fork...join_none

In reply to rohit_kumar:
Not sure what you mean by
clk[j]_in
. Perhaps you meant
clk_in[j]
.

Once that is fixed, your code does not wait for
enable
to be high; it only checks it once on the first clock cycle. You probably want

  @(posedge clk_in[k] iff (enable[k]==1)) begin