how can i reset my mira advance shower?

From the manual ( Which you DID read or, if you didn't have, you DID search for - I found one in the first page of Google results at:

http://www.mirashowers.co.uk/onlinecatalog/pdf/1170168_w2_a_mira_advance_atl.pdf

Its both the installer instrucitons and the users guide.

Read pages 11 and 12 of the users guide.

and also pages 23-25 inclusive of the installaers guide.

If you are not 110% sure of EXACTLY what you are doing get a professional in.

Water and electricity are lethal

X
February 2015