Getting $subject must be of type string error on checkout

Hey Guys,

Very new to CS-Cart and im not a very savvy front end guy. (Heads up). I imported all of our old clients from the old site (not CS-Cart) into cs-cart via the DB. Now occaisionally I get an older client that logs in, places his order and when he tried to complete his checkout he gets hit with a 500 “Service Unavailable” error. This has been happening more frequently and I cant figure out what the issue is. When I view Source on the error page, im always getting this error… and I hav eno idea what it means… or how to fix it. Any help would be greatly appreciated.

TypeError

Message
preg_match(): Argument #2 ($subject) must be of type string, array given

Error at
app/lib/vendor/ezyang/htmlpurifier/library/HTMLPurifier/Lexer.php, line: 368

Backtrace
File:app/lib/vendor/ezyang/htmlpurifier/library/HTMLPurifier/Lexer.php
Line:368
Function:preg_match

File:app/lib/vendor/ezyang/htmlpurifier/library/HTMLPurifier/Lexer.php
Line:329
Function:extractBody

File:app/lib/vendor/ezyang/htmlpurifier/library/HTMLPurifier/Lexer/DOMLex.php
Line:50
Function:normalize

File:app/lib/vendor/ezyang/htmlpurifier/library/HTMLPurifier.php
Line:213
Function:tokenizeHTML

File:app/Tygh/Tools/SecurityHelper.php
Line:268
Function:purify

File:app/functions/fn.users.php
Line:1247
Function:sanitizeHtml

File:app/functions/fn.users.php
Line:1249
Function:{closure}

File:app/functions/fn.users.php
Line:1147
Function:fn_store_profile_fields

File:app/functions/fn.cart.php
Line:1275
Function:fn_store_user_profile_fields

File:app/functions/fn.cart.php
Line:1544
Function:fn_update_order

File:app/functions/fn.cart.php
Line:10194
Function:fn_place_order

File:app/controllers/frontend/checkout.php
Line:397
Function:fn_checkout_place_order

File:app/functions/fn.control.php
Line:722
Function:include

File:app/functions/fn.control.php
Line:458
Function:fn_run_controller

File:index.php
Line:25
Function:fn_dispatch

Thank you in advance.

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