Suppose I lost my cellphone~

Friend : Hey, did you find your phone?

me : Oh, I found it. was in my bag. Actually I couldn't find because it was really in the bottom of my(or "the") bag.

I thought I had lost it, but I have found it. I'm feeling good. Thanks for your concern.

Notes:

1.Ever sentance needs a subject, this is why I added "it".

2. "Actually" is a word you use when correct someone, and you're not correcting anyone here.

3.You just don't need "really". It's not wrong per say, it's just awkward.

4.You need to use "in" to show location of the cell phone and "the" because it is a specific location.

5.You could use "my" or "the", but you need one of those to specify which bag.