I want to perform insert and upadate operation on Account on same record by using following query but It inserts two accounts with different descriptions
Account acct = new Account(Name = 'practice upsert',phone ='675122',description = 'updated record 1'); INSERT acct;
Account acct2 = new Account(Name = 'practice upsert',phone ='675122',description ='updated record 2');
upsert acct2 account.fields.ID;
How can I insert and update same record using IDLookup?