sub-menu problem

I have an accordion menu on page one working perfectly, including sub-menu items.
Submenu items are not indented and do not have list-bullets. (I think that is the default(?) but I did this some time ago and have forgotten whether I somehow modified that with CSS).

With a new accordion menu on page 2 (separate and different, with its own CSS) the sub-menu items do not behave as expected.

Problems are:
1. Sometimes are already open , not hidden
2. Hidden or not, they are left-hand indented, and have a lot of white-space (margin-bottom) between them and next items, both unwanted.
3. They have unwanted list-bullets

I have found a way to remove list-bullets and remove indentation and list-bullets by giving sub-menu items a class name and modifying this with CSS, like this:

.submenu_item {
list-style: none;
margin-left: -5.7% !important;
}

However, I can’t find any way to remove bottom white-space. Margin-bottom changes only makes the element move upwards onto the item above.

I also haven’t improved the items sometimes being hidden, sometimes not.

I can’t understand why the first accordion is OK and this one not? Is it a bug?

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