What Is the "real world" event(s) behind each security that you have in your Investment Account and what Quicken "Action" was used to get that security into the Account? The reason I ask is that some events, like mergers and acquisitions, spin offs, split offs, stock splits, and other "corporate actions" can mean that not only do you have to create a basis amount for "new to you securities/shares", you also have to adjust the bases of of other shares in your Account.
In the simplest situation - and maybe that's the one you face - you created you Account in Quicken some months or years after creating the "real world" Account and the initial download of transactions didn't include every transaction in the Account from the time you opened it with the financial institution, resulting in Placeholders to get the number of securities in Quicken aligned with the number of securities actually held at the financial institution. In that case one approach would be to edit that Placeholder, making it an "Added" action transaction, and enter the basis of those shares that didn't show up in that initial download.
If you have Placeholders in your Account then it should show a number of shares equal to that of the broker. If you simply want to get your total basis correct without "lot" information, (I assume you know your total basis), click on the blue "Enter cost" that's in the Placeholder, and enter the "missing" amount. using the average cost of those particular shares or the total cost for those shares. That should get your basis in line with what the broker is showing.
Do that for each security.
