Christina Inglett, Machine may require cleaning/descaling pg.26/27 in manual(1st link below), could be a bent/collapsed hose inside machine, pump may require priming or pump may be failing, Below find trouble manual, shooting guide, disassembly guide. Good luck. I hope this helped you out, if so let me know by pressing the helpful button.
http://www.partsguru.com/user/Rio%20Vapore%20SIN006_ENG.pdf
[[Starbucks Barista Troubleshooting]]
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