This is a common issue. You can see that your transaction has 184 inputs here Transactions - Zchain and as a results some miners are excluding it.
See Unconfirmed transaction or Unconfirmed transaction after 4 days; getting worried for more explanation and a link to potential solution.
There is also a few Github issues open including this one: 11-day delay in mining a transaction with 498 transparent inputs · Issue #3167 · zcash/zcash · GitHub