NRF Failed to generate jwt on Thingy 91 with location example

Question

Hi, I am currently learning to retrieve location using thingy 91 and location example from nrf SDK. When I run it, I got this message (below).

[00:10:00.546,142] <inf> lte_lc: Network connection attempt timed out
+CEREG: 0
[00:10:00.564,941] <inf> lte_lc: Using fallback network mode
+CEREG: 2,"5320","01B3A85B",9
+CSCON: 1
+CEREG: 1,"5320","01B3A85B",9,,,"11100000","00101100"
Connected to LTE
Waitin+CEDRXP: 5,"1001","1001","0011"
%XTIME: "21","22216011215021","00"
g for current time
Requesting location with short GNSS timeout to trigger fallback to cellular...
[00:10:25.811,035] <inf> nrf_cloud_pgps: Checking P-GPS header: Schema version:0, type:0, num:0, count:0
[00:10:25.821,563] <inf> nrf_cloud_pgps:   size:0, period (minutes):0, GPS day:0, GPS time:0
[00:10:25.830,932] <wrn> nrf_cloud_pgps: One or more fields are wrong
[00:10:25.848,968] <err> nrf_cloud_jwt: Failed to generate JWT, error: -8
[00:10:25.856,872] <err> location: Failed to generate JWT, error: -8
[00:10:25.872,436] <err> nrf_cloud_jwt: Failed to generate JWT, error: -8
[00:10:25.880,340] <err> location: Failed to generate JWT, error: -8
+CSCON: 0
[00:10:33.104,919] <wrn> location: Timeout occurred
[00:10:33.126,159] <wrn> location: Failed to acquire location using 'GNSS', trying with 'Cellular' next
%NCELLMEAS: 0,"01B3A85B","42003","5320",48,6246,119,74,23,632236,631518
[00:10:33.165,893] <inf> location: No neighbor cell information from modem.
[00:10:33.209,320] <err> nrf_cloud_jwt: Failed to generate JWT, error: -8
[00:10:33.232,299] <err> nrf_cloud_rest: Failed to auto-generate JWT, error: -8
[00:10:33.255,889] <err> nrf_cloud_rest: Could not format HTTP auth header, err: -8
[00:10:33.279,846] <err> location: Failed to acquire location from multicell_location lib, error: -8
[00:10:33.305,297] <err> location: Location acquisition failed and fallbacks are also done
Getting location failed

Requesting location with the default configuration...

After doing some research, I got stucks and got several question.

1. How do I solve those failed to generate jwt error: -8 on there? I already check on this thread Failed to generate JWT even ask it, but looks like the url is dead or it gives me page not found.

2. Why I can't get any GNSS data from the example?

Thanks for reading this. Really appreciate with all the answer. Thanks.