Pressure cook

I bought a packaged cook set at this company and i dismantling the lid of my pressure cook- please note NOTHING IS BROKEN, after I washed it, food went into one of the rubber bands and I washed it of course, now it’s hard to put it back together because it looks complicated. As expected, it’s releasing pressure and not working anymore because I couldn’t put the seals back together. The manual is not clear and there’s nothing on the internet as to how I can put it back. I was told I have to pay R300 for a pick up and a certain amount to get it fixed. This is what I’m going to deal with every time I wash my pressure cook. I don’t know, am I expected to leave it to rot !!!!!