Toilet blade/flapper not closing - Dometic Master Flush 8700

[Gonna_Wander]

I noticed water had drained from the toilet shortly after flushing. Poked around a little and it seems the blade/flapper is stuck in the open position, meaning it does not close after flushing. I can feel the thin circular opening where I assume the blade retracts into during flushing. I put some Vaseline around the thin opening, but it seems the blade is stuck in the retracted position.

I am not familiar with how this new-to-me macerator operates and the only manual I found was for installation and there were not troubleshooting topics to cover this.

Any thoughts?

["007"]

I guess there comes a time when its necessary to clean the toilet with a small hooked tool to clean the slots were the blade enters into.
Use to have to do on older toilets at times would be surprised what you might find, its politely called "gunk" if you have a lot money, I guess you can always buy a new toilet.
They use to supply a small tool with hook.
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[BFlinn181]

A toothbrush can also be used to clean the groove the rubber seal sits in. Make sure the toothbrush is marked "Out of service." Rubber gloves and a nose clip is also handy for this job.