Boohoo Refused My Full Refund and Has No Contact Number for Real Support

Boohoo's customer service approach absolutely irritates me. Expecting a refund of £78.50, I returned many goods to their warehouse and was confirmed in writing. Though the error is obviously on their end, Boohoo is now advising me to straight forwardly address the problem with my bank after I have just received £30.20. To further the situation, they have no contact number, hence I am left depending on pointless emails. I have been caught in a maddening cycle of telling different agents about the problem for the past three weeks, as though none of them could view my earlier messages or grasp the circumstances. I have to wait additional business days each time, only to get the same unproductive answer. This continuous backtracking has been somewhat taxing.