Issue with pivot_longer() ".value" code.

General
#1 
I am trying to recreate data pivoting with '.value' code:
source to original:
 https://www.youtube.com/watch?v=qaksmQabMUI&list=PLmNrK_nkqBpL9STHqSod2LGwciLk9TXZ1,  
11 minute.

I think I got everything in order to make it work but  after pivoting I get Error:

'Expected 2 pieces. Missing pieces filled with `NA` in 2 rows [1, 2].'
Here is the data frame:
      x     y  b_x   b_y name
1  9010 10515 9020 10525    1
2   935   585  925   575    2
3  6825  7970 6835  7980    3
4   730   700  720   690    4
5   945   975  955   985    5
6  1565  1520 1555  1510    6
7  2120  1025 2110  1015    7
8  1520     1 1510    -9    8
9   985     1  975    -9    9
10 1360  1085 1350  1075   10

Than i run code as follow:
```{r}
data %>% 
  pivot_longer(
    cols = -name,
    names_to = c(".value", "pro"),
    names_sep = "_"
  )
name  pro    x     y     b
1     1 <NA> 9010 10515    NA
2     1    x   NA    NA  9020
3     1    y   NA    NA 10525
4     2 <NA>  935   585    NA
5     2    x   NA    NA   925
6     2    y   NA    NA   575
7     3 <NA> 6825  7970    NA
8     3    x   NA    NA  6835
9     3    y   NA    NA  7980
10    4 <NA>  730   700    NA
Expected 2 pieces. Missing pieces filled with `NA` in 2 rows [1, 2].