Trout,
Try setting it up differently, you may have had a funky set up?
If that fails and you really feel its stretched, try a simple hand wash. Dunk it in the sink, roll it around some, gently ring it out, hang it out to dry for a few hours in the breeze. Washing may re-align the fibers, and help your issues.
My hammocks may have stretched some, but are usually more comfortable after a few days of hanging.
A ridgeline really helps control where you like the sag, do you have a ridgeline on your hammock?
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