Retrenchment letters not attended

On the 1 st of Oct 2020 i went to Edgar's Benoni Lakeside Mall to submit my retrenchment letter i went to customer service desk they told me they no longer taking letters i should email it myself to hollard they gave me email adress of *** and *** on the 2nd of October nd 5th i email my documents retrenchment letter, certificate of service and copy of ID since then i never received any call or respond from both emails, today to my surprise I got sms stating that i didnt made payment next monthbi must pay double and interest i dont understand why should i pay double with interest while i emailed both with on separate occasions before due date of payment. My ID is *** J O Boh