text filter option not available

Hi,

I have a column that contains identification names for a list of company assets. The names comprise of letters and numbers. I want to filter it so that it only displays the names that have 32 characters as these refer to a particular category.

However when I apply a filter the 'text filter' option is not shown. The property of the column is 'text' and was 'General' previously but it wont display 'text filters' whatever the property type.

I have no other filters applied to this column to prevent the text filter from showing in the filter menu.

I have googled this but cannot find the answer..

Any help appreciated,

Thanks,

Rob.