Merida espresso 300 no PAS

[aaaaaku]

Hello! I have a big problem. My motor is Shimano Steps and I changed my front gear on my bike to a bigger one to get higher speeds pedaling but as I now understand Shimano Steps is not letting me do that. I have forgotten what error number whas sowing before but i have remounted everything to original but it wont give me asistance. I can read the speed but its not assisiting. What can I do? / Karl. Love From Sweden