Multiselect Dropdown Not Showing All Options

I have a multiselect dropdown that is searching a data type that I currently have about 30,000 items for but it only seems to be displaying things that start with the letters a through to c and it stops there. The aim is for the user to type a word or two so that it will only show a few results that match but if what the user types is later in the alphabet then it just says no results.

I have been trying words later in the alphabet like ‘Strawberry’ and I know for a fact that I have things in the database that match that but it just no results so I tried scrolling through all results without typing anything and that’s when I saw that the results are stopping at results starting with C.

Has anyone had this issue before? Is there any way to get around it?