Been getting phonecalls everyday by shop who supplied me goods on credit,I paid 1st payment on the day of agreement,on day of delivery 6days later the shop phoned me to say delivery was on that day and also said payment due,it wasn't for 3more days.the day after rhey phoned me again I said that payment wasn't due for another day.they have phoned me everyday since,they have also been to my house and phoned my sister.I haven't been to pay through embarrassment and I feel quite intimidated by them I understand I sighned an agreement and I am at fault for not paying,are they allowed to harass people this way?