Should have looked up the yarn, I assumed it was the thicker yarn but this pattern calls for thread weight. Start over, just use the stitches and dimensions with a larger hook. Chained 48, for a total of 100 stitches per row after the corner increases.
Bag is 13 inches wide x 15 inches high, 8 trebled rows.
Decided to do an inline handle. The final ball of yarn had an undyed section so I left that for the second last row, finished with a slip stitch for edging.
Handle is chain 20, skip 15 stitches.