Lumps on gums where no teeth,

I am a vigorous brusher so may be worsening this condition. Over many years I lost the five leftmost teeth on my upper left and similar on the right apart from one molar. Over time some little hard lumps came up on the gaps mainly on the chewing edge and the inner cheek side. I can’t remember the name given to the condition when I asked but was told it was not a concern. Over the past year they have got bigger and they swell overnight and decrease again as the day goes on. I am aware of them but they are not exactly painful. I rub Gengigel or Bonjela on them.
I have asked this previously but without replies from other with it.