query in solving parallel to serial conversion process

ml = 4;

i have done this conversion process but error is coming

% Parallel -> Serial conversion
Rx_sel_data = reshape(Rx_para_data,1, para*ml);

Rx_sel_data_LS = reshape(Rx_para_data_LS, 1, para*ml);

Rx_sel_data_LMMSE = reshape(Rx_para_data_LMMSE, 1, para*ml);

**Error is like this:-

??? Error using ==> reshape
To RESHAPE the number of elements must not change.

Rx_sel_data = reshape(Rx_para_data,para, para*ml);
 **

how can i get rid of this problem?

[Walter Roberson]

What does

size(Rx_para_data)
disp(para)
disp(m1)

show ?