To get Android out of the mix as a possible cause, try a Windows laptop also, both via WiFi and with an Ethernet cable.
Since https://www.tp-link.com/uk/products/details/cat-4691_TL-MR6400.html says "Requires no configuration - just insert a SIM card and turn it on to enjoy high speed internet access." it should work after you reset the router to factory conditions. If not, it's seems a warranty issue. So back to the shop and let them show it works or get a new one free.
I have this problem:
I have a SIMcard data and if put it into the iPad and shear the connection I can connect via WiFi my PC to internet and connect to Skype4Buissines. If I use the same SIMcard in a WiFi 4G router everythink is fine but Skype4Buissiness that wonn't work (and maybe VPN, I didn't try yet)
I check on the router option and I can't see anything wrong. What you suggest? Have you an idea of what could I check? To resume: same SIMcard different devices: Work with: iPad and iPhone Doesn't work with: Android and TP-LINK TL-MR6400
thank you for all your suggestions. ![]()

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