Hide blank values in matrix view

[rax99]

I have 2 tables containg call_IDs with a specific call direction (so table1 contains incoming, table 2 outgoing)

Table1:

Call_ID	Direction	Attempt	Cold	Warm
1	In	101	81	29
2	In	119	147	90
3	In	152	37	70
4	In	65	65	116
5	In	102	127	144
6	In	15	33	18
7	In	89	45	33
8	In	105	35	119
9	In	36	98	115
10	In	90	66	22

Table 2:

Call_ID	Direction	Attempt	Cold	Warm
1	Out	22	120	18
2	Out	119	117	88
3	Out	40	16	39
4	Out	94	82	90
5	Out	110	76	51
6	Out	139	124	49
7	Out	113	59	114
8	Out	130	13	59
9	Out	19	69	55
10	Out	50	7	38

I have a 'bridging' table for the call direction to join the tables.

When creating a matrix, I get the columns being duplicated on each of the grouping category, and displaying blank values like below;

Clearly these blanks highlighted above should not be appearing. How do I get rid of these?

Note. This is a simplified version of a more complex table/data structure with more calculations etc so unfortunatly I cannot combine the In/Out tables (which does fix the issue in fact)

See attached pbi file for full example.

PBI_File