You cannot change the priority once added. Instead what you can do is…when you want to retry remove queue retries and manually in the system exception catch block add a new item with same details but with setting the priority to high
you have to do it in the same way as you did for add queue item …but the only difference is instead of adding the variable you will add Name = transactionitem.Specificcontent(“Name”).Tostring in the arguments of add queue item for each specific content
Example
Kindly note: when only setting the Priority it will clear other field (e.g. SpecificContent). So everything what is to keep is also to include within the body payload