I have two switches for one light. One is a dimmer switch and other is single pole switch
You need smart switches. Period.

A smart switch can handle this problem easily. Anything else will require busting up drywall and laying new cable - possibly /4 cable to the switch loop owing to needing to support both a 3-way and provide neutral. Let's sidestep that, eh? 

Why would anyone wire it this way? My guess is, the now-dimmer location started out only as a place to tap power for the light, and the switch loop was meant to be the only switch. 

Use a smart switch with smart 3-way capability and wireless remote

You put the smart (dimmer) switch at the current dimmer location (with neutral). The line up to the lamp becomes switched-hot and neutral.  That means the switch loop to the other switch is pretty useless.  That is why you need a wireless battery powered remote which matches to the smart switch. Generally these look exactly like wall switches or dimmers, but can be mounted to the wall with sticky tape. 

Selecting particular models is off-topic here, so I leave it to you to find an a) smart b) dimmer that c) accepts wireless remote and d) talks to whatever WiFi scheme you are interested in.  Don't buy mail order; make sure the part that touches mains power has a UL listing, CSA, ETL or other NTRL.  CE is not one, and is the mark of cheap Cheese junk that you are not allowed to use in mains wiring.  CCC, FCC and RoHS are also used to fool you. 

Or, use a smart module in the lamp box

In this case, you can use the wiring in and out of the lamp as always-hot and neutral.  That can power any wired smart switch of your choice coughInsteoncough, provided the switches can communicate with the module via powerline or wireless signaling,