I've a problem with index:reindex on Product Price, after an composer update && install
Any idea about this error?
As Attached screenshot not approved yet so I can not see but as per exp most of the times error occuers after update with redis so
Try to disable redis In app/etc/env.php
Comment line responsible for caching using redis and flush cache.
If this work and you want to use redis you can read documentation on how to setup redis server from beginning.