It has taken some people a long time but succeeded eventually for others it a sign things are not working. Possible reasons:
Some earlier versions of Chia Blockchain had a wallet sync issue. I presume you are using the latest?
You may be syncing poorly or not at all. Is your full node synced, but your wallet not synced?
Are you port forwarding to your full node machine from your external connection?
How many connections do you have on the full node page and are they sending/receiving?
In the folder C:\Users\yourname.chia\mainnet\db how large is the database file? I am fully synced, at the time of writing, and the DB folder is 13.4GB. Once you have most of the database, you can back it up or copy it to another machine to save you all the syncing time but do so with Chia fully shutdown, or it will be corrupted.
Be aware that to sync requires significant CPU resource as well and a robust internet connection. On a Ryzen 3600 I see the CPU having a regular rhythmic (every few seconds) double digit load while processing the blockchain and creating the multi-gigabyte db. Think in day or days terms to completion depending on those factors. And over time, the full db creation gets ever bigger and therefore longer to finish.
Probably not though a combination of a very slow computer and a very slow internet connection, and a lack of port forwarding resulting in packets not reaching the intended farmer machine could conceivably result in a failure to ever sync.
There are people using Raspberry Pis that manage, I synced an ACEPC T6 stick PC back in May but connected to a fairly decent internet connection.
Just keep plodding at it.
It helps a lot.
Shut down chia on both computers.
Copy the entire contents of the /DB folder to the machine that is struggling, then restart chia on both machines.
Are they both full nodes? On the same local network? This can work for some but for others its a problem as the packets do not always end up at the right machine. It can be better to run 1 full node and multiple harvesters.
I remember trying to resync my farmer from scratch a few weeks ago. After 2+ days, I gave up and just restored a good copy of the wallet and DB. Still took me another day to get the wallet and DB in sync. My internet is slow and the farmer server is slow.