Is there a way to run the same payload multiple times?
It's not entirely clear what your scenario is, but there are a couple ways you might do this:
1. Add test suite logic to your test suite that causes the test to loop multiple times
2. Put the payload in an external file, and then reference the file from multiple client tools in SOAtest
Create a global tool that is configured to send your payload and then create multiple tests that reference the global tool?