Building a simple app to bridge one token with PoS SDK

Hi there,
Im building an app to bridge a token from and to mumbai from goerli. every thing worked well until the withdrawExit call.
im following this guide:

what worked:
on goerli: approve token to bridge and deposit
on mumbai: withdrawStart
after that i saved the burnResult.getTransactionHash(), switched to goerli again and on calling the withdrawExit with that hash i got this error:

message: "Could not retrieve transaction. Either it is invalid or might be in archive node."
type: "invalid_transaction"

I can confirm that transaction hash exists on the mumbai side:
(tried it two times)

im completely stuck right now, any help would be very welcome.

I found my issue, just had the wrong chainID on the child provider. the SDK uses the parent provider for almost all actions, but for the withdrawExit it needs to use the child one.

I would check out zbyte, making simple apps like this can be done in seconds with their platform.