Why Is My Beer Flat?

Question:

I made 5 gallons of a strawberry blonde beer with an unhopped wheat malt, hallertauer hops and strawberry extract..when bottling I used 22 ounce bottles and put a teaspoon and a half of priming sugar in each bottle and then capped them and let them sit for 3 weeks.

So far every bottle I opened has great body but is flat and has no head. Anyone know what could be going wrong?

Answer:

I normally use online calculators when calculating carbonation and figuring 2.5 volumes of CO2 for a 5-gallon batch at 70°F, you’d need 4.5 ounces of corn sugar.

Unfortunately, I don’t know if that’s more than the 43.5 teaspoons that you used. There are 48 teaspoons in a cup and you used slightly less so seems like you might be off in your calculation.