Website Error Cannot Use String


I am about to change servers and testing reveals it isnt quite operating correctly and getting the below error, Anyone help ?
Thanks
Uncaught Error: Cannot use string offset as an array in /home/yhuijknh/public_html/app/functions/fn.catalog.php

it seems to be related to feature variants but Im unure where to start

PHP Fatal Error

Message
Uncaught Error: Cannot use string offset as an array in /home/yhuijknh/public_html/app/functions/fn.catalog.php:7596
Stack trace:
#0 /home/hiviscou/public_html/app/functions/fn.catalog.php(3691): fn_get_allowed_options_combination(Array, Array, ‘’, 0, Array, Array)
#1 /home/hiviscou/public_html/app/functions/fn.catalog.php(7757): fn_get_default_product_options(‘24277’, true, Array)
#2 /home/hiviscou/public_html/app/functions/fn.catalog.php(617): fn_apply_options_rules(Array)
#3 /home/hiviscou/public_html/app/controllers/frontend/categories.php(101): fn_gather_additional_products_data(Array, Array)
#4 /home/hiviscou/public_html/app/functions/fn.control.php(700): include(‘/home/hiviscou/…’)
#5 /home/hiviscou/public_html/app/functions/fn.control.php(456): fn_run_controller(‘/home/hiviscou/…’, ‘categories’, ‘view’, ‘’, ‘’)
#6 /home/hiviscou/public_html/index.php(25): fn_dispatch()
#7 {main}
thrown

Error at
app/functions/fn.catalog.php, line: 7596

Backtrace

What version of cs-cart and PHP?

Might try running with php 7.2

Cheers Tony , the new server was set to php7.1, needed to go back to 7

doubtful. What version of cs-cart are you running. Send me email and I'll try to take a look.