I am applying CRUD FLS on task object fields and also I have provided read and edit access to task for site user profile. Even checked with sharing settings as 'Controlled by parent'.
But still when I debug that field is accessible but not having updateable access so it's not entering inside if loop. Below is the code for reference
for (Task objTask : taskList){
if(Schema.SObjectType.Task.fields.Message_Status__c.isAccessible() && Schema.sObjectType.Task.fields.Message_Status__c.isUpdateable()){
objTask.Message_Status__c = taskStatus;
}
}