Our main WAN switch port randomly locks up every few weeks

We have a rack at the datacenter with a 1Gb fiber line running to it. That connects to a Dell 2024 switch SFP port, access mode vlan, then there's two copper ports on same access vlan going to two HA Sonicwalls. We also have a fiber P2P line that connects into the same switch, different access vlan, with two more ports going to the HA Sonicwalls.

Every few weeks our WAN port is seemingly locking up. Completely stops responding. I then haul my ass up to the datacenter and reset the switch, and everything comes back up. This is what we know so far:

• Replaced the switch
• Replaced the SFP module
• Verified config
• Do not believe it's a Sonicwall issue as the Sonicwall still seems up and fine during the outage
• Bringing the port up/down again fixes the issue (unplugging and plugging the fiber into the SFP)
• The P2P line plugged into the same switch continues to function, zero issues (it's from the same provider as well)

We've talked to the ISP and they want to have the datacenter check their fiber cross connect, clean it, replace jumpers, etc. I'd also like to have the ISP move us to another port on their end just in case that's the problem, but they're not wanting to do that, don't think it's necessary. I think it's necessary though. These outages are causing us major problems and they should do that simply out of good faith, IMO, NOW rather than after next time we have an outage.

Is there anything else I should be looking for here?? I'm no network engineer here so if there could be some advanced networking issue going on here I may not be aware of it.