There are two problems here: one serious that you don't think you've met yet, and the other causing the problem you have noticed.
The serious one is simple: never concatenate strings to build a SQL command. It leaves you wide open to accidental or deliberate SQL Injection attack which can destroy your entire database. Always use Parameterized queries instead.
When you concatenate strings, you cause problems because SQL receives commands like:
SELECT * FROM MyTable WHERE StreetAddress = 'Baker's Wood'
The quote the user added terminates the string as far as SQL is concerned and you get problems. But it could be worse. If I come along and type this instead: "x';DROP TABLE MyTable;--" Then SQL receives a very different command:
SELECT * FROM MyTable WHERE StreetAddress = 'x';DROP TABLE MyTable;
Which SQL sees as three separate commands:
SELECT * FROM MyTable WHERE StreetAddress = 'x';
A perfectly valid SELECT
DROP TABLE MyTable;
A perfectly valid "delete the table" command
And everything else is a comment.
So it does: selects any matching rows, deletes the table from the DB, and ignores anything else.
So ALWAYS use parameterized queries! Or be prepared to restore your DB from backup frequently. You do take backups regularly, don't you?
And that's related to the problem you have noticed: never store data in a text based filed unless it is text based data. Always use an appropriate datatype: DECIMAL for money, INT for integers, and DATE, DATETIME, or DATETIME2 for dates.
This is causing your problem because string based comparisons are always based on the first different character that is encountered when comparing the two strings. Which means that dates in string format compare very badly: "01/01/2021" is before "31/12/2020" because '0' is before '3'.
And there is more: even if you store dates ad DATETIME then unless you pass DateTime values from your app as a parameter, you will still get errors because string formatted dates have to be interpreted by SQL as DATETIME first, and they don't get any context and make assumptions about the format: is "01/02/03" the 1st Feb 2003, or 2nd Jan 2003, or 3rd Feb 2001? They are all valid: US, European, Japanese / ISO formats.
You need to change your whole app to fix the first problem, then change your database to fix the second as well.