Zebpay — Deductions of holdings without my consent

I've purchased 10k worth of SHIB coins on Zebpzy exchange on feb22...i.e 3500000 coins in total...i've bought this coin to hold long term...when i logged in back to check now i was literally shocked to see 1382000 coins as my holding balance...to check what happened to my holding i conted the zebpay customer support ...they replied that i was debited as custodial fee and is non refundable...even if there was a custodial fee...how could they debit 70% of my investment as custodial fee...this is totally unacceptable...i want a refund of my investment...if they fail to...i wanna sue them fr tht...