I applied and got the visa approval letter for 1 month single entry visa (from April 17 to May 17). But my plan changed and I will enter Vietnam about 5 days later (April 22). Does this approval letter work? If so, will I have 1 month in Vietnam or I must exit Vietnam by May 17 if I use this letter?
Be kindly informed that there is no problem if you actual entry date is later than the date issued in the approval letter. You are allowed to enter Vietnam 5 days later (April 22) without re-apply visa. However, the letter of approval is valid through 17 May that even you arrive later, your visa will be expired on May 17 as stated in the approval letter.