When i am sewing the thread from the bobbin keep bunching up in the bottom of the material

bunching of thread under the material is an indication of insufficient tension of the needle thread
increase the needle tension until the threads meet at the center of the materialbeing sewn

make sure that the bobbin carrier is fixed in properly
make the needle thread tension a lot tighter

Could be many things. Old blunt needle, wrong tension, wrong needle and thread for the material. Have you got the same thread in bobbin and needle?Also is needle and bobbin threaded correctly?
best wishes

This sounds a lot like you've forgotten to lower the presser foot. (this leaves the tension discs open and causes serious issues below the material.) Double check that and if still having issues post again.

try a different needle
here's a link to a free manual from singer
http://www.singerco.com/uploads/download/1199_8770-efs.pdf
some machine can't handle thick fabric & some can
rethread the machine top & bobbin
clean under the needle plate & in the bobbin area
make sure the thread has not come off the thread take up lever

remove the thread and bobbin.
take out your manual and follow the exact instructions for threading and inserting bobbin.

If this does not help check the tension on the top(the number should be about mid way).
If it is too low it will bunch up on the bottom.

First make sure your bobbin is wound tight and not "mushy." Next re-thread your upper thread.

1.needle in backward
2.needle bent or blunt
3.rethread
4.check for lint or thread fragments in bobbin area

Thread the machine with different color thread for the needle and the bobbin, then see which color is bunching up.Ill bet it is the top thread.

Hello,
Here are some solutions to try.

* Re-thread your machine
It may be threaded incorrectly.

* Raise your feed dogs If your machine has this feature.

* When you start to sew a seam, hold the upper and bobbin thread tails back and out of the way as you sew your first couple of stitches. This will keep them from getting caught in your machine.

I hope this helps.