A PHP Error was encountered

Severity: Notice

Message: Trying to access array offset on value of type null

Filename: models/Product_model.php

Line Number: 639

Backtrace:

File: /var/www/html/application/backend/models/Product_model.php
Line: 639
Function: _error_handler

File: /var/www/html/application/backend/models/Product_model.php
Line: 543
Function: countProductlikes

File: /var/www/html/application/frontend/controllers/Products.php
Line: 793
Function: getProductDetailByAsin

File: /var/www/html/index.php
Line: 336
Function: require_once