RAK3172 no-ipex module with Low level development don't work

I am currently using the low-level development of the RAK3172. It operates normally when using the RAK3172 IPEX module. However, when using the RAK317 no-IPEX module, it behaves abnormally. The Tx done event does not occur after data transmission. What should I check?

There is no hardware difference between RAK3172 Ipex and RAK3172 NON-Ipex.

Or are you talking about RAK3172 and RAK3172-SiP?
They are different and code for the RAK3172 does not work on the RAK3172-SiP.

Here is the link to a guide for RAK3172-SiP: RAK3172-SIP custom firmware - #2 by carlrowan