SunupAmerica LLC review: Solar panels

I signed a contract with sunup America on 4/26/23 I was not informed about a 3 day cancel fee. The three days ends 4/30/2023 which is a Sunday. I have no way of contacting this company today and they will charge me $1329.00 if I do not mail them their cancel document. The sales man went throgh the contract never mentioning a cancel fee. They have no fax number listed and I cannot contact them until tomorrow. I did send them an email but I have no proof of sending the email to cancel. I just want to cancel this contract I also gave them a check for $3000.00. Please Help!