Pivot Period weeks not running in sequence

[Puggwash63]

I have a pivot chart that shows Periods and Weeks as shown below, but I want them to run in sequence and find that P10 W1 % P10 W2 does not run after P9 W4.
I have looked at everything in the chart and looks ok.
Wonder if any of you can help


P1 W1
P1 W2
P1 W3
P1 W4
P10 W1
P10 W2
P2 W1
P2 W2
P2 W3
P2 W4
P3 W1
P3 W2
P3 W3
P3 W4
P4 W1
P4 W2
P4 W3
P4 W4
P5 W1
P5 W2
P5 W3
P5 W4
P6 W1
P6 W2
P6 W3
P6 W4
P7 W1
P7 W2
P7 W3
P7 W4
P8 W1
P8 W2
P8 W3
P8 W4
P9 W1
P9 W2
P9 W3
P9 W4


Many thanks

Pugg