Expired visa

Hi my name is Lori I'm from Canada my Turkish visa expired 3 days ago August 21 and I have decided to stay in turkey until September 29 how do I go about extending my visa

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Hi Lorii, is it a visa or a residence permit ?

You cannot extend a visa. Once a visa is expired, you have to leave Turkey. The only way you can extend your stay is to apply for a residence permit, but you would need to do that before your visa expired.

Since you have overstayed your visa, you will have to pay a fine when you depart Turkey. Because your overstay is more than ten days, you will also receive a re-entry ban.  The re-entry ban will probably be for three months considering the amount you will have overstayed when you leave.