On Dec 26th, 2017, I created a DGB wallet using "Digibyte Go."  I sent some DGB to the wallet.  Now, 3 years later, I'm trying to access them and the wallet balance says zero.  However, it shows the transaction from 2017 as "received."  When I look up the address on the block explorer, the coins are there.  The wallet lists the same address but the balance says zero. Why is this wallet not working properly?  Also, it seems I did not save a back up phrase because 3 years ago, I didn't know.