Help cpap water reservoir

[Kimp]

I have a cpap i use to travel with and have not used it in a while. It was difficult to take the top off my water reservoir for H5 with yellow seal. Cleaned it and now it will not close enough to snap all 4 sides close. Does the yellow rubber seal go in the lid or on the bottom edge of water tank itself. I don't remember. Currently it is stuck in the lid of reservoir.

[Pugsy]

What brand and model?